Hummer H3 P0357: Coil Pack “G” Malfunctioning – Diagnosis

P0357 is a generic OBD II diagnostic code that indicates an issue with the ignition coil “G” (it’s the seventh cylinder). Specifically with the primary or secondary wiring circuits. If your Hummer H3 has thrown P0357, it may be accompanied by P0307 (this code indicates a misfire in cylinder seven).  Addressing P0357 should take care … Read more

Hummer H3 P0715: Symptoms, Causes, & Diagnosis

P0715 is a generic, and somewhat rare OBDII trouble code.  If your Hummer H3 has P0715, it indicates there is a communication error with the sensor that measures transmission input speed.  Common Causes: A bad transmission speed sensor, shift solenoid, wiring issues, and even low/no transmission fluid can all cause P0715. P0715 Definition: Input/Turbine Speed … Read more

Hummer H3 P0688: Meaning, Causes, + Diagnosis

P0688 is a relatively rare OBD2 trouble code. It’s a generic code, meaning that it has the same definition for any vehicle made for the 1996 model year and up.  This includes the Hummer H3. The most common causes of P0688 are a bad PCM power relay or a wiring issue between the PCM and … Read more

Hummer H3 P0685: Meaning, Causes, + Diagnosis

P0685 is a somewhat rare OBDII trouble code. It’s a general code, so it has the same meaning for the Hummer H3 as any other vehicle. It indicates that the circuit that provides power to the PCM is not functioning properly.  Most of the time, P0685 will cause your H3 not to start, which leaves … Read more

Hummer H3 P0661: Meaning, Causes, & Diagnosis

P0661 is a relatively rare OBD2 trouble code.  It indicates that the electrical reading coming from your Hummer H3’s intake manifold tuning valve control circuit (on the bank 1 side) is below its specified operating range. While P0661 is a generic code, so it has the same definition for all vehicles. P0661 Definition: Intake Manifold … Read more

Hummer H3 P0660: Meaning, Causes, & Diagnosis

P0660 is a somewhat common OBDII code.  It’s generic, so it has the same meaning for the Hummer H3 as it would any other vehicle made for the 1996 model year and up.   This code indicates that there is an issue with the bank 1 side of the intake manifold valve tuning control circuit. Common … Read more

Hummer H3 P0627: Meaning, Causes + Diagnosis

P0627 is a somewhat rare and generic OBD2 trouble code, which means that it has the same meaning for the Hummer H3 as it would any vehicle made for the 1996 model year and up. In the H3, P0627 is most commonly caused by a wiring issue, bad fuel pump, or defective CAN bus.  P0627 … Read more

Hummer H3 P0621: Meaning, Causes, + Diagnosis

P0621 is a generic OBD2 code, which means that it has the same meaning for the Hummer H3 as it would any other vehicle. However, it can be challenging to diagnose due to the necessity of removing the instrument cluster. OBD2 P0621 indicates an issue with the circuit that controls the generator lamp, which is … Read more

Hummer H3 P0622:  Meaning, Causes + Diagnosis

P0622 is a somewhat rare OBD2 trouble code.  It’s a general code, meaning it has the same definition for the Hummer H3 as it would any other vehicle.  This code indicates the generator field coil control circuit is malfunctioning.  It can be a challenge to diagnose. P0622 Meaning:  Generator Field F Control Circuit Malfunction “Generator … Read more

Hummer H3 P0650: Meaning, Causes & Diagnosis

P0650 is a somewhat rare OBD2 trouble code.  It is generic, meaning that it has the same definition for any vehicle, including the Toytoa H3 Your H3’s PCM will set P0650 when it detects an issue with the malfunction indicator lamp (MIL), also commonly referred to as the check engine light.   The biggest issue … Read more