2015 duramax lml

Jan 10, 2023
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I read, I read and I read and I understand less and less, I have a 2015 LML with codes in the brake, mass air and ambient temperature sensors, the truck does not run more than 70 and has no power, and I have read that they fixed it with a tuner, someone around louisville kentucky who could help me? I can move 5 or 6 hours if necessary. I wait for an answer
 

2004LB7

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Dec 15, 2010
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Where are you measuring them at? Ground or the other end of the harness? Ground will only correctly test one pin, the ground. The others will be running through the ECM and the readings will be of little use. Best results are from pulling the connector on the ecm and measuring the resistance of the harness. And a voltage drop test with a load would be good too
 

2004LB7

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Dec 15, 2010
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With your meter. One leed goes to the ECM side and the other leed goes to the sensor connector. Then the meter reads the resistance of the wire on the harness

For items like the brake pedal sensor you put both leeds on the ECM side and measures what the pedal resistance is

With the ECM connector hooked up, you can measure the voltage to ground at the sensor connector to see if it is correct.

If all looks good and you have a solid ground and supply to the sensor then that leaves the sensor or ECM as the next item that could be at fault.
 
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Jan 10, 2023
34
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so of the 3 plugs of the ecm which would it be? Once disconnected, do I measure, for example, the pin on the harness side and the pin on the ecm that matches? would that be with the truck off?
 

TheBac

Why do I keep doing this?
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Apr 19, 2008
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Since you obviously have no working knowledge of these trucks or how to diagnosis/repair ability, why the heck arent you taking this truck to a competent shop to get it fixed?
It is next to impossible to help from afar. This forum is NOT "Fixya".
 
Jan 10, 2023
34
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That is what I want. A workshop!! I already took it to the dealer, several electrical ones, a workshop in Indiana and nobody finds a solution