Possible causes – Repair other codes first Tech notes If the P1381 code is set with other codes, repair other codes first and then clear the code. When is the code detected? If a loss of communication occurs which causes

Possible causes – Reprogram TCM and recheck code– Replace Transmission Control Module (TCM) Sensor/body assembly one piece Symptoms – Engine Light ON (or Service Engine Soon Warning Light) P1684 GMC Description The Transmission Control Module (TCM) power up the temperature

Possible causes – Reprogram TCM and recheck code– Replace Transmission Control Module (TCM) Sensor/body assembly one piece Symptoms – Engine Light ON (or Service Engine Soon Warning Light) P1685 GMC Description The Transmission Control Module (TCM) power up the temperature

Possible causes – Reprogram TCM and recheck code– Replace Transmission Control Module (TCM) Sensor/body assembly one piece Symptoms – Engine Light ON (or Service Engine Soon Warning Light) P1686 GMC Description The Transmission Control Module (TCM) power up the temperature

Possible causes – Secondary Air Injection check valve bank 2– Secondary Air Injection (AIR) pump electrical circuit fault – Blocked Secondary Air Injection (AIR) system – Faulty Secondary Air Injection (AIR) pump When is the code detected? The P1415 code

Possible causes – Secondary Air Injection check valve bank 2– Secondary Air Injection (AIR) pump electrical circuit fault – Blocked Secondary Air Injection (AIR) system – Faulty Secondary Air Injection (AIR) pump When is the code detected? The P1416 code

Possible causes – Sensor using 5 volt reference line shorted to ground– Circuit short to ground When is the code detected? If the voltage is out of tolerance, the PCM will set DTC P1639. Symptoms – Engine Light ON (or

Possible causes – Trailer towing may set code– Check transmission fluid level– Internal transmission fault Symptoms – Engine Light ON (or Service Engine Soon Warning Light) P1870 GMC Description Transmission is in 4th gear with Torque Converter Clutch (TCC) engaged

Possible causes – Turbocharger Boost Control Position Sensor harness is open or shorted– Turbocharger Boost Control Position Sensor circuit poor electrical connection– Faulty Turbocharger Boost Control Position Sensor When is the code detected? The ECM has detected a high voltage

Symptoms – Engine Light ON (or Service Engine Soon Warning Light) P1130 GMC Description The Heated Oxygen Sensor (HO2S) is monitored for switching. The test fails when the HO2S does not switch due to circuit or fuel at or exceeding

Symptoms – Engine Light ON (or Service Engine Soon Warning Light) P1131 GMC Description A Heated Exhaust Oxygen (HO2S) sensor indicating lean at the end of a test is trying to correct for an over-rich condition. The test fails when

Symptoms – Engine Light ON (or Service Engine Soon Warning Light)

Symptoms – Engine Light ON (or Service Engine Soon Warning Light)

Symptoms – Engine Light ON (or Service Engine Soon Warning Light)

Symptoms – Engine Light ON (or Service Engine Soon Warning Light)

Symptoms – Engine Light ON (or Service Engine Soon Warning Light)

Symptoms – Engine Light ON (or Service Engine Soon Warning Light)

Symptoms – Engine Light ON (or Service Engine Soon Warning Light)

Symptoms – Engine Light ON (or Service Engine Soon Warning Light)

Symptoms – Engine Light ON (or Service Engine Soon Warning Light)