2007 Chevrolet Trailblazer 6-Cylinder Multiple Fault Codes: P2101, P1682, P0030, P0036, P0102 - Still in MIL Mode After Passlock and Ignition Replacement
My 2007 Chevrolet Trailblazer with a 6-cylinder engine is stuck in Mil (Malfunction Indicator Lamp) mode despite replacing the passlock sensor. While that resolved most of the error codes, the vehicle remains in MIL mode. Current diagnostic trouble codes include: - P2101: TAC Motor Circuit Range/Performance - P0030: Bank 1 Sensor 1 O2 Sensor Malfunction - P0036: Bank 1 Sensor 2 Heater Circuit Malfunction - P0102: MAF or VAF Circuit Low Input - P1682: Ignition 1 Voltage Less Than 10 Volts I have thoroughly cleaned all connections from the battery to the fuse box and verified major ground points. The issue persists. Additional observation: When I clear the codes using a scan tool while the engine is running for approximately two seconds, the vehicle temporarily runs normally, but after reset, it immediately returns to poor performance and reactivates all codes. I also have P0053 and P0054 O2 sensor faults. I've checked fuses #28 (IGN1, 15A under hood) and #47 (IGN0, 10A under rear seat), both of which show no voltage when powered. I suspect a potential voltage drop during cranking — should I test for ignition circuit voltage while cranking? Any insights on diagnosing P1682 or TAC motor issues in this model would be greatly appreciated.
P1682 indicates the ECM detects a voltage difference greater than 3V between the two ignition circuits for less than 1 second. BBBind.com has detailed schematics available. Confirm that one of the ignition inputs to the ECM is below 10 volts. Also, was the ignition switch replaced along with the passlock sensor? This could be critical.