LEXUS GX 460 2012 CRANK NO START.
Good day guys, I was called to come see a Lexus GX460 2012, with a 1UR-FE engine.
It was a crank no start problem. If you notice the instrument cluster, the check engine light is not on.

Plugged in my scan to retrieve some codes, found out, I was unable to communicate with the Engine control module I checked all fuses that powers the module they were all ok. So my next line of action was to go to the ECM to test if the voltage were getting to the ECM.

So, I studied the system I'm about to tackle with service manual and schematics. The 1st frame is the detailed information of the ECM connectors.
The 2nd frame indicates what each pins does, in this case, all the voltages the ECM needs to work.

It was a tad difficult to get to where the ECM was, but i managed to get to it. I carried out voltage measurements at the ECM, and all voltages were present.

At this point, this is where most "rewire" condemns the ECM, and tell client to get another ECM. For me, it's not, this is just the beginning, there's still more test to be carried out. The next one is called reference voltage test.

The ECM is a computer that accepts inputs from sensors e.g camshaft sensor, crankshaft sensor, Engine coolant temperature sensor, knock sensor etc., process this input data based on programs written to the microprocessor inside it and output it through actuators e.g motors, Ignition coils, Nozzles, solenoids.
In other for the ECM to recieve data from these sensor, it sends out a reference voltage to the sensor, the sensor returns a voltage based on what is been sensed, it could be temperature, flow, position and many more.

A simple analogy will be, take a value from 0-5(reference) 0 bin the coldest and 5 bin the hottest what's your temperature then you may reply with 2.5 indicating your temperature is somewhat normal
So, the ECM sends out 5V or 12V this values are determined by car manufacturers

I tested this voltage at the manifold absolute pressure sensor and at the ECM itself, for this particular vehicle it's 5V and it was present which indicates our engine is well and alive, so question remains why isbour vehicle not still starting.
After seeing my Reference is present, I carried out another test called network integrity test, that's a discussion for another day, it was ok too.
I was running out of options, so I decided to open the ECM.

I found corrosion and some bad capacitors in the PCM. I cleaned it out and swapped out the bad capacitors( I've solid background in microsoldering from Macbook repairs), my phone died on me, couldn't take any pictures or videos.
Viola got the vehicle working again.


If you carefully take a look at 1st frame Engine and ECT say not equipped, 2nd frame says no fault code, my phone went off after capturing the second frame I couldn't get a video of the engine running. The engine started and ran smoothly.

The pictures might be incoherent, I don't know how to use this NL well
But I have a well detailed with pictures and videos thread on twitter, here is the link to the thread
https://twitter.com/biltronix/status/1543329470999937027?t=b47glIUEbdCaEFxy7jnf1A&s=19

Would have been really nice to upload those pictures here tho.

Billiebaba:
LEXUS GX 460 2012 CRANK NO START.
Good day guys, I was called to come see a Lexus GX460 2012, with a 1UR-FE engine.
It was a crank no start problem. If you notice the instrument cluster, the check engine light is not on.

Plugged in my scan to retrieve some codes, found out, I was unable to communicate with the Engine control module I checked all fuses that powers the module they were all ok. So my next line of action was to go to the ECM to test if the voltage were getting to the ECM.

So, I studied the system I'm about to tackle with service manual and schematics. The 1st frame is the detailed information of the ECM connectors.
The 2nd frame indicates what each pins does, in this case, all the voltages the ECM needs to work.

It was a tad difficult to get to where the ECM was, but i managed to get to it. I carried out voltage measurements at the ECM, and all voltages were present.

At this point, this is where most "rewire" condemns the ECM, and tell client to get another ECM. For me, it's not, this is just the beginning, there's still more test to be carried out. The next one is called reference voltage test.

The ECM is a computer that accepts inputs from sensors e.g camshaft sensor, crankshaft sensor, Engine coolant temperature sensor, knock sensor etc., process this input data based on programs written to the microprocessor inside it and output it through actuators e.g motors, Ignition coils, Nozzles, solenoids.
In other for the ECM to recieve data from these sensor, it sends out a reference voltage to the sensor, the sensor returns a voltage based on what is been sensed, it could be temperature, flow, position and many more.

A simple analogy will be, take a value from 0-5(reference) 0 bin the coldest and 5 bin the hottest what's your temperature then you may reply with 2.5 indicating your temperature is somewhat normal
So, the ECM sends out 5V or 12V this values are determined by car manufacturers

I tested this voltage at the manifold absolute pressure sensor and at the ECM itself, for this particular vehicle it's 5V and it was present which indicates our engine is well and alive, so question remains why isbour vehicle not still starting.
After seeing my Reference is present, I carried out another test called network integrity test, that's a discussion for another day, it was ok too.
I was running out of options, so I decided to open the ECM.

I found corrosion and some bad capacitors in the PCM. I cleaned it out and swapped out the bad capacitors( I've solid background in microsoldering from Macbook repairs), my phone died on me, couldn't take any pictures or videos.
Viola got the vehicle working again.


If you carefully take a look at 1st frame Engine and ECT say not equipped, 2nd frame says no fault code, my phone went off after capturing the second frame I couldn't get a video of the engine running. The engine started and ran smoothly.

The pictures might be incoherent, I don't know how to use this NL well
But I have a well detailed with pictures and videos thread on twitter, here is the link to the thread
https://twitter.com/biltronix/status/1543329470999937027?t=b47glIUEbdCaEFxy7jnf1A&s=19

Very good I'm impressed

Impressed. You will make it easily with this level of expertise and attention to detail. The youths who shout unemployment every time are just lazy. There is a wide knowledge gap and deficiency in automobile repair. Just arm yourself with knowledge which these days are free on internet. Get required tools and see yourself bridge that gap and rake in money.

chukel:
Impressed. You will make it easily with this level of expertise and attention to detail. The youths who shout unemployment every time are just lazy. There is a wide knowledge gap and deficiency in automobile repair. Just arm yourself with knowledge which these days are free on internet. Get required tools and see yourself bridge that gap and rake in money.

Thanks a lot chief, I’m down to fix any electrical issues with any brand especially European brands

Billiebaba:

Thanks a lot chief, I’m down to fix any electrical issues with any brand especially European brands

followed you on twitter. Also asked a question about rear Sam. Where is your location.

chukel:
followed you on twitter. Also asked a question about rear Sam. Where is your location.

Lagos, Ebute Metta

chukel:
followed you on twitter. Also asked a question about rear Sam. Where is your location.

Lagos Ebute Metta