₦airaland Forum

Siena:
[color=Blue]Does a light bulb tell you what voltage you're reading? Does it tell what the polarity is? We're talking bulb here, not an LED.

Just so you know, a bulb has a hell of a lot more internal resistance than a digital multimeter. Measure across the 5V reference outputs from an ECU, and you could kill it. Same goes for measuring V in sensitive modules like instrument clusters, ABS modules, TCU's etc.

I have not had a test bulb amongst my test equipment for over 2 decades. I do have an LED power probe, and I seldom use even that. Voltmeters, oscilloscopes or picoscopes are all safe to use, and I rely more on these as modern systems become more complex, and measured voltages become smaller. Try measuring 900mV with a 12V 10/21W tungsten bulb, and see what the results are.

A technician who will not invest in a digital multimeter that starts from as low as £4.99 is a cowboy.[/color]

Voltmeters, oscilloscopes or picoscopes - how much do these cost for DIYs not professional level?

isn't the voltmeter embedded in the DMM? Do I need a dedicated voltmeter?

After I called a local electrical tech to help me fix a short which I earlier posted about.

I stayed back to observe him and every time he performed an action my heart would sink.

He kept throwing away factory rubber shields, cutting wires here and there, and probing pins

The next day my MAF failed, I do not know if it is a coincidence or it is his use of 12V via the test bulb to keep probing the various components

The one that made me not ask him to come back was when he wanted to start working on the ECU while the battery terminals were still connected.

Thankfully, he came in the afternoon and when he said he would have to come back the next day to complete, we haggled over pricing

Then I paid him 50% and he left, I gathered all the insulators he threw away and tried to return everything as closely as possible to how it was when it left the factory and didn't allow him to touch the ride again.

I think that his work destroyed my MAF, I cannot say for certain.

But I cannot allow him to cost me an ECU in the name of fixing shorts

Forgive my backyard statistics

But it seems to me that 99.9% of local car electronics/electrical technicians use only a test light to try to troubleshoot issues

When service manuals usually recommend multi-meters for tests?

Which would you rather have?

Can a test light substitute for a multi-meter?

I think for me the answer is multi-meter. But just how do they get to sort out issues with just a test light and without consulting factory manuals?

I want to learn oooo

greenhulk:
I really can't say. But Benin-ore road is in a pretty bad shape, there are big pot holes and even if u are an expert at dodging potholes, u can't dodge all of them.

I lost a brand new Michelin tire costing almost 30,000.00 in use for less than a month due to a pothole on a trip

I will create a thread on it when I have time and also update my other incomplete threads on my trips as my notes are intact, just no time to put them up since am kinda busy

Personally I think all this emphasis on tires without emphasis on eradicating or minimizing potholes by the authorities is extremely unfair to the populace in a dwindling economy

Interestingly i kept a similar nearly brand new dunlop tire that suffered the same fate two years ago and I notice something, the tear is almost identical

so here is my new way of handling potholes (before i used to dance around them at about 80km/hr) but am revising the speed down because the potholes have worsened and multiplied

1. slow down to less than or about 50km/hr to 60km/hr on pothole infested roads ( but get back the time by hitting 200km/hr on good roads)

2. try to drive as slow as possible into them if you cannot dodge them;

3. also do not use maximum permissible tire pressure so the tire can flex a bit;

4. ensure your shocks are in tip top shape but that does not mean you should not slow down since there is not enough time for the shock to act and you tire has no choice but to bear the brunt of much of the pressure;

5. brake as much as possible before entering a pothole but ensure you are NOT holding the brakes into the pothole cause you will lose the tire


This is why Lokoja Okene road is an invitation to party for kidnappers, drive fast and lose your tires or wreck your suspension, drive slow and be double-crossed

May God save us

Piyke please use Enugu, i travel alot, the road through enugu is in much better shape than the road through edo overall, you will still pass through Kogi and some parts of Lokoja, and maybe Okene but you cannot compare the state of both roads, the Enugu route is way way better

Which MPV? 1996 - 1999 OR 2000 - 2001 OR 2002 - 2006

Which Location?

What happened before it started jerking?

What have you done to fix it so far?

Been away sorting out some financial issues.

So now I got a little time to take this further:

1. IMRC 1 and PCM 42
-- if faulty can trip on P1512 and P1520
RESULTS OF OPEN CIRCUIT TESTS:

Passed

BUT

when I tested PCM 42 with IMRC 3 and IMRC 6, I can observe that there are shorts between the following
IMRC 3 and PCM 42 as well as between
IMRC 6 and PCM 42


2. IMRC 3 and Body Ground
-- if faulty can trip onP1512
RESULTS OF OPEN CIRCUIT TESTS:

Passed



3. IMRC 5 and PCM 3
-- if faulty can trip on P1512
RESULTS OF OPEN CIRCUIT TESTS:

Passed

BUT

when I tested PCM 3 with IMRC 3 and IMRC 6, I can observe that there are shorts between
IMRC 3 and PCM 3 as well as between
IMRC 6 and PCM 3

4. IMRC 6 and PCM 91
-- if faulty can trip on P1512
RESULTS OF OPEN CIRCUIT TESTS:

Passed

BUT

when I tested PCM 91 with IMRC 1, IMRC 2, IMRC 3 and IMRC 5, I can observe that there are shorts between
IMRC 1 and PCM 91 as well as between
IMRC 2 and PCM 91
IMRC 3 and PCM 91
IMRC 5 and PCM 91

5. IMRC 2 and Main Relay Terminal D
-- if faulty can trip on P1512 and P1520

RESULTS OF OPEN CIRCUIT TESTS:

Passed

BUT

Should there be continuity between IMRC 2 and all the 4 pins of the relay?

I ask because there is continuity between
IMRC 2 and Relay terminal D
IMRC 2 and Relay terminal B
IMRC 2 and Relay terminal C
IMRC 2 and Relay terminal A

I think that my problem is as a result of either wires touching other wires or touching grounds that they ought not to, i.e., short circuits and ground faults!

dioman:
Uyo - Katsina (16hrs.

Day 1 (12 hrs

Uyo - Ikot Ekpene - Umuhia(Abia State) - Enugu - Nsuka(Enugu state) - Otupo (Benue State) - Ekiti State - Ajakuta(Kogi State) Lokoja (Kogi State) - Abuja - Kaduna.

Day 2 (4hrs

Kaduna - Zaria - Funtua - kankia - Mani - Dutsema - Katsina.

Mazda 626.

How is this route today in 2016? is it safe to drive given the current state of insurgency in the country? Please advice

There are six short circuit tests:

1. IMRC 2 and BODY GROUND
-- This is part of Mazda's recommended IMRC Actuator Inspection, no code specified


2. IMRC 1 and BODY GROUND
-- This is part of Mazda's recommended IMRC Actuator Inspection, no code specified

3. IMRC 1 and POWER SUPPLY
-- This is part of Mazda's recommended IMRC Actuator Inspection, no code specified

4. IMRC 5 and BODY GROUND
-- This is part of Mazda's recommended IMRC Actuator Inspection, no code specified

5. IMRC 5 and POWER SUPPLY
-- This is part of Mazda's recommended IMRC Actuator Inspection, no code specified

6. IMRC 6 and POWER SUPPLY
-- This is part of Mazda's recommended IMRC Actuator Inspection, no code specified

There are five open circuit tests:

1. IMRC 1 and PCM 42
-- if faulty can trip on P1512 and P1520

2. IMRC 3 and Body Ground
-- if faulty can trip onP1512

3. IMRC 5 and PCM 3
-- if faulty can trip on P1512

4. IMRC 6 and PCM 91
-- if faulty can trip on P1512

5. IMRC 2 and Main Relay Terminal D
-- if faulty can trip on P1512 and P1520

cocoduck:
good if you have an oscilloscope, this would have been a breeze for you, well, since it is a low amperage circuit, use your meter to do a continuity test between those pins and their corresponding pins in the PCM connector, but if were me. I would rig up something to test it using a test light, or if you have a test light that is 200ma or less, it is computer safe.

Seems to me that an oscilloscope is for big boys, how much does one cost?

I have been using my meter and I will share with you the results to help me zero in on what is going on

I have yet to use a test light, I need to learn how to use one.

basically from the above, the tests required to be done to resolve this issue can be grouped into three:
1. Open circuit tests
2. short circuit tests
3. malfunction tests (connector/IMRC/PCM)

In the next few posts, I will share my findings from conducting the first two sets of tests

Here is a description of the second error code resolution procedure:

DTC Full Name:
DTC 1512 Intake Manifold Runner Control (IMRC) Shutter valve close stuck

DTC Detection Condition:
The PCM monitors the voltages of IMRC monitor circuit. If the PCM terminal 3 voltage within 1.6V - 4.9V for 3.15 seconds when the IMRC valve is open, the PCM determines that the IMRC system has a malfunction


POSSIBLE CAUSES:
1.Open circuit in wiring between the main relay terminal D (harness-side) and IMRC actuator terminal 2 (harness-side)

2.Open circuit in wiring between IMRC actuator terminal 1 (harness-side) and PCM TERMINAL 42 (harness-side)

3.Open circuit in wiring between IMRC actuator terminal 3 (harness-side) and BODY GROUND

4.Open circuit in wiring between IMRC actuator terminal 5 (harness-side) and PCM TERMINAL 3 (harness-side)

5.Open circuit in wiring between IMRC actuator terminal 6 (harness-side) and PCM TERMINAL 91 (harness-side)

6.Connector or terminal malfunction

7.IMRC Malfunction

8.PCM malfunction

Here is a description of the first error code resolution procedure:

DTC Full Name:
DTC 1520 Intake Manifold Runner Control (IMRC) Shutter drive circuit malfunction

DTC Detection Condition:
The PCM monitors the voltages from IMRC control circuit. If the PCM terminal 42 voltage is 3.0V or below unless circuit is grounded during operation, the PCM determines that the IMRC system has a malfunction


POSSIBLE CAUSES:
1. Open circuit in wiring between the main relay terminal D (harness-side) and IMRC actuator terminal 2 (harness-side)


2. Short to ground circuit in wiring between the IMRC actuator terminal 1 (harness-side) and PCM TERMINAL 42 (harness-side)

3. Open circuit in wiring between IMRC actuator terminal 1 (harness-side) and PCM TERMINAL 42 (harness-side)

4. Connector or terminal malfunction

5. IMRC Malfunction

6. PCM malfunction

These pictures show how the IMRC looks like!

Both the sealed box and the connector that takes current from the IMRC box to the PCM

olenyi:
That it cracks at some point during the day is not an LNB problem. Have a good installer check your dish. it must have shifted slightly without you knowing. Even a ''strong'' branded LNB lasts as long as the ''follow come'' DSTV LNB when it comes to tracking Eutelsat W4/W7. The installer should be able to isolate the root cause why your LNB goes bad.

My regards.

I guess you are right after all, because today it isn't cracking.


I wonder why it did yesterday, and I recall when it happened like this last December, I was told it is an LNB problem and so I got to get a new one, from your explanation, it is good that I kept the old unit, cause it might not be faulty after all, the guy just wanted to make a quick hit, if my guess is right.

cocoduck:
I suggest you take it to somebody that has the tools to disassemble the dashboard and you do the repairs yourself, or if you have the tools, you can try it your self, disconnect the battery first, before attempting it, start from the steering wheel, then remove the components and label or mark them so you can easily put them back, then go to the radio and use pry bars (plastic preferably) to pry those panels, they rarely use screws to hold them, they use tabs instead, then remove the glove box then the passenger air bags, take your time to find the screws, they are usually hidden from view, or under some panels, the main dash is held by 15 or 16mm nuts.
You will need patience, lots of it, to be able to bring this thing down, common sense is also required a lot, and if you can, do it with somebody, mark and label every nut and bolt and screw and every other thing, so that you will easily figure it out when you assemble it .

Am fighting two codes P1520 and P1512 which could be mechanical or electrical in origin. I suspect that mine is an electrical fault.

It relates to what is called Intake Manifold Runner Control

It is a pretty common problem on Ford and Mazda vehicles that share common engine designs including but not limited to Ford Focus, Ford Mustang on the Ford side and Mazda MPV, Mazda Miata and Mazda 5/6/CX-7

cocoduck:
I suggest you take it to somebody that has the tools to disassemble the dashboard and you do the repairs yourself, or if you have the tools, you can try it your self, disconnect the battery first, before attempting it, start from the steering wheel, then remove the components and label or mark them so you can easily put them back, then go to the radio and use pry bars (plastic preferably) to pry those panels, they rarely use screws to hold them, they use tabs instead, then remove the glove box then the passenger air bags, take your time to find the screws, they are usually hidden from view, or under some panels, the main dash is held by 15 or 16mm nuts.
You will need patience, lots of it, to be able to bring this thing down, common sense is also required a lot, and if you can, do it with somebody, mark and label every nut and bolt and screw and every other thing, so that you will easily figure it out when you assemble it .

You suggest the following:

1. Get help from someone who can disassemble the dashboard BUT fix it myself
---Let me see how far I can with your help over the internet before trying extreme measures like disassembly

2. Fix it myself if I have the tools
---So far I have a multi-meter which am pretty good at using, a test light I have never used, an appetite to learn, and couple of YouTube videos that I have digested

3. Always disconnect the battery first before working on the circuit
---I have always practiced this, I vividly recall destroying a couple of fuses several months ago when I did some work without doing so, so I know this one

4. A work-through for dealing with the dashboard removal
---Let me work you through all I have done so far before confirming that this indeed needs to be done

5. Common-sense and patience, labelling and marking so reassembly will be painless.
---Absolutely lots of this is required plus taking notes along the way so you can undo what you have done should anything go wrong.

Thanks so much for your support

After serving me for years, my LNB died last December.

I replaced it on December 2, 2015 and now today April 16, 2016 it has gotten the same fault. Now that is a little over 4 months! Gush!!

It plays well at night and cracks/crackles during the day as soon as the sun is hot.

I have come to the conclusion that I got a cheap unreliable Chinese knock-off

So how do I get one as qualitative as the one that comes with the DSTV dish?

Thanks anyone and everyone in advance

Question is relevant because I once had a blowout, lost 2 tires and the nearby tire guy on the express 2km away had just 215/65R16

it was a choice between going back to the nearest town about 70km away or using three 215/60R16 and one 215/65R16

It could happen to anyone...so the question isn't entirely out of place...

...as soon as I got home I got the normal tire and gifted the out of place to the nearest roadside tire guy...

cocoduck:
just use a wiring diagram, which can be downloaded free from bbbind.com. But try to repair the original wires first, if it is impossible to repair then you can rout another wire.

I have a wiring diagram, and indeed I have been using it.

This is opportunity cost, I really want to repair the original wires but the route they are taking between the engine and component requires I remove the entire engine and the dashboard just get at them not to talk of fixing them.

The more components that need to be taken out and but back the greater the potential of causing some trouble, and I am not a mechanic...LOL

So I would rather cut the wires a few inches from the PCM and run new wires through insulation through the firewall to the component.

Indeed as they say short circuits are hard to find, open circuits are so easy to find.

Am not using a test light but a multi-meter.

As this is my first time, I am naturally cautious since I do not wish to cause any further damage in the name of solving a problem.

TUDEXautoCARE:
Body ground is the any metal part around the vehicle which is grounded or connected to the negative battery terminals. Ground in vehicle is like the Earth in the building electricals terms.

Thanks so much.

So based on your explanation above and the extract below:

SHORT CIRCUITS

A short circuit occurs when electricity finds a short cut" from positive to negative; it is the result of a bare spot on the wire contacting part of the metal car body. The windings in electric motors can also short. Short circuits are hazardous be- cause they create sparks, burned wires, and blown fuses. They are more difficult to locate with a test light than open circuits.

1. Disconnect the suspected circuit at all points where it is joined by connectors (you'll need the wiring diagram for this).

2. Attach the clamp of the tester to the hot side of that circuit's fuse and touch the probe to the other side of the blown fuse. If the light goes on, the short is between the fuse and the first disconnected connector.

3. If the light doesn't go on, connect the first connector and touch the probe to the fuse holders again. If the light goes on, the short is between the first and second connector.

4. If the light again does not go on, repeat the process until the section of the wire with the short is isolated.

Which I have taken from this site: http://www.drivegreen.com/Auto_Service_5_Wiring_Lighting.htm

Can I safely cut out the part of the wires that go into the wiring harness from the engine compartment into the passenger area where the PCM is located and run new wires from the PCM to the component, provided that I ensure that each wire goes exactly into where I cut the old one everything should work?

Cause I can see that three different wires are shorted:
1. power supply is shorted to body ground
2. Monitor Signal to PCM is shorted
3. Monitor Signal ground is shorted

If I can get wires that match the colors of the pre-existing wires and run them from the component to the PCM all should be ok?

The I have isolated the fault to between the PCM and a connector, from the other connector end to the component is all clear?

Looking forward to your further comments

I have a faulty piece of electronics in my vehicle and one of the testS I need to do is to test for continuity between one of the pinouts and body ground.

I know my way around a multi-meter and have successfully tested for continuity between the PCM and the equipment at fault.

What I cannot do is to test for continuity between one of the pins and body ground because I do not know where to find body ground.

Please kindly help me find this elusive fellow? BODY GROUND!



LOL

THANKS

Thanks for all the comments.

Let me set the records straight.

I normally run 215/60R16, and they are all due for a change - all 5 including the spare.

Am low in cash (more commitments at the moment than cash to cater for them all, so I got to prioritize, and you know tires are the number safety equipment especially in these rains, and the ever present danger of being fined by the FRSC), so I spoke to a friend who gave me 2 brand new 205/60R16.

I know all the story about mismatched tires, so I have never run mismatched tires, cause it can screw the ABS in an emergency maneuver.

So I have two 205/60R16 and was about to buy two more 205/60R16 that's when the vendor asked the above.

So I wanted to get a second/knowledgeable opinion cause I have always run 215/60R16 and am not exactly pleased with having to run the 205/60R16 but I cannot also allow them go to waste.

Wrong brand new tire size that fits is way safer than the correct/recommended tire size that is bare, so I might end up with the 205/60R16 until the next tire change

So that's the background of the story...

is the above combo safe or unsafe?

I want to buy tires.

I have 2 brand new 205/60R16.

I want to buy 2 more 205/60R16.

Vendors says why not buy 215/60R16.

Should I listen or should I run?

...What do you guys think

Please recommend a tire that can do 45,000 miles minimum and ideally 60,000 miles.

Mainly highway miles across Nigeria's length and breadth.

Highway driving 75%/ City Driving 25%

Usual cruising speed anything between 62 mph (100km/hr) to 100 mph (160 km/hr)

Am currently considering the following

Michelin Pilot MXM4 50,000 miles ( 6 years warranty)

Michelin Energy LX4 50,000 miles ( 6 years warranty)

Michelin Primacy 55,000 miles ( 6 years warranty)

Michelin Energy Saver A/S 65,000 miles ( 6 years warranty)

Has anyone gotten their brand new tires to get the above mileage before replacement

Michelin Defender 90,000 miles (6 years warranty) but I am not considering it because I do not like the T speed rating, minimum acceptable speed rating is an H, in case I need to short bursts of up to 130 mph (209 km/hr)

Journey was postponed to 14032016, and i returned 15032016.

As far as fuel scarcity is concerned, we have Abuja and the rest of Nigeria

What is happening in abuja is make-believe, the situation out of abuja, from Kogi to Calabar is heart-rending. All the major marketers, Total, Conoil, Forte, Mobil, Oando, even NNPC mega stations do not sell fuel outside abuja. Fuel is sold for 140 at stations and as much as 250 in the black market. Indeed count yourself lucky to live in abuja

Is it not an irony that they sell in abuja and no where else down to the south? Does it not tell you that something is not adding up?

So postpone any unessential travel until you confirm that the situation has improved or carry three times the money for fuel.

Let me say this for now, there is still a cabal, but the media is keeping quiet about it, and Nigerians are suffering a great deal. No wonder people talk of chains and not change nowadays, it is no joke! The pain and suffering is real!!

I will gather my thoughts and complete the story.

Got to catch up with stuff back here in abuja.

I got some more pictures this time around

Content coming soon!

isn't it funny.

I kept fighting a stored code P0171 and a pending code P0174.

After having gone through all the the above listed, turns out that the engine was sucking air via an improperly seated oil dipstick.

Now what many people do not realize is that the engine is a giant air pump. And that the are approved and unapproved inlets and outlets for air to come in and go out.

Well, I have known that for a while.

But it never occurred to me that the engine would attempt to suck air from the oil dipstick tube and so keep throwing my diagnosis off the mark.

Well, my dipstick handle broke so I did not seat it properly and it never occurred to me that I was creating a lean condition by so doing

What surprised me is that is not one of the things included in the list of things to look out for in AllDataDIY

You can read more about the P0171 here http://repairpal.com/OBD-II-Code-P0171-and-P0174

shedyman:
Hello Nairalanders, my Toyota Corolla popped up the check light engine, after it was scanned it came up with the P0171 code.

The car hesitates and has a jerk like movement when I press on the accelerator, my mechanic advised I changed the MAF sensor and I kindly need an assistance as to where I can get the sensor in Abuja.

Thanks in anticipation of your directions

clean the MAF first, replacement should be last resort

check resolution steps at obd-codes.com

discussed how i resolved mine here: https://www.nairaland.com/2879665/abuja-calabar-8-2-16-calabar-abuja/1 ( 2nd page, last few posts)

Lexusgs430:
To answer you simply, is your performing at its best optimum in its present state? (NO)
Is your car's performance likely to suffer on it's present state? (yes)
NB: If you have a slightly fractured hip, does it mean you cannot walk a mile? (NO)
What it means is, you would walk the mile, but with pains all over your body. Requiring strong pain killers like tramadol, zormoph or morphine.
Your car is requesting pain killers, give it now before the slight fracture turns into a major visit on the surgeon's table!!!

LOL at the analogy, makes sense to me.

EgunMogaji:
Dude fix your car, you don't want exhaust fumes in your car.

Actually, I keep fixing it and it seems the guys here do not know how to make the perfect weld, it always leaks.

I know because if I start it in the morning and check under, I can see some water dripping from the weld points.

I actually decided to cut and replace the offending section with new pipe sections.

And this time around, I want to try electric welding, cause the gas welders have terribly disappointed me time without number

honmusa:
Fuel mileage and performance will suffer at low RPM but the effect will be negligible at high RPM .
U will need to understand the concept of ''back pressure on exhaust system '' to understand this analysis.
what is a back pressure ? A back-pressure is a restriction to flow of exhaust flow ,it is intensionally introduced by car manufactures this to create more powerful exhaust velocity for faster exhaust discharge . A backpressure can likened to a spray nozzle of garden hose supplying water . Small level of backpressure is needed for better performance @ low RPM however ,too much of it will hurt performance and gas mileage . However backpressure whether small or big is undesirable @ high RPM.
The question is now is 'how does a leaking exhaust pipe affect backpressure '
A leaking exhaust pipe is similar to the analogy of a garden hose without a spray nozzle(backpressure ) on it, If you let the water just run unrestricted out of the hose it flows out limply at a rather slow rate. However, if you take your finger(backpressure ) and cover part of the opening, the water will spray out at a much much faster rate.In the same vein ,a exhaust pipe @ low RPM that is leak -free will have more powerful exhaust velocity to give your engine due to the presence of backpressure thereby creating better performance and fuel mileage .However a leaking exhaust is similar to pipe without back pressure ,exhaust tends to flow at lower velocity which will have great impact on fuel mileage and performance .
But at high RPM, little or no back pressure is required for effective discharge of exhaust as the engine need to breathe better thereby making the effect of exhaust leak on performance negligible compared to low engine RPM .
So exhaust leak might not have so much effect on your engine performance and mileage @ high speed compared to low speed .At low speed it will definifitely hurt performance and fuel.

Thanks for this detailed explanation! I also love the analogy.

Kind of agree,one more question, might this be why it uses more fuel at stops?

can electric arc welding do as good a job if not better than gas electrode welding?

KingRex1:
I'm no car specialist bt frm my lil knowledge on car tech.
If ur injector is fine, engine is sound, carries out a good combustion process, pistons in good shape, alternator on point.
I see no reason why ur exhaust should pose as a prob or cause increased fuel consumption. It only discards waste emissions from 'already' burnt fuel nd energy.
.
If ur ass leaks, it wont increase ur hunger level..

Thanks so much for chipping in!