P16A7 on 2018-2020 Chevrolet Traverse (L, LS, LT, RS, Premier, High Country) — Engine Controls Ignition Relay Feedback Circuit 2
1 vehicles · 1 makes · $150-$900 repair
Most Reported On
P16A7 is an OBD-II diagnostic trouble code meaning “Engine Controls Ignition Relay Feedback Circuit 2.” A General Motors manufacturer-specific code (Chevrolet, GMC, Buick, Cadillac). The ECM receives three ignition-voltage feeds: two supplied by the engine controls ignition relay and one by the ignition main relay. It continuously compares the two monitored ignition-voltage circuits and sets P16A7 when the difference exceeds 3 volts for more than about 1 second. Because the ECM's own power supply is in question, symptoms range from a check engine light with no drivability complaint to hard starting, stalling, or a no-start. Note that P16A7 is manufacturer-specific — on non-GM vehicles the same code number carries a different definition, so confirm the make before diagnosing. This code is most commonly reported on 2018-2020 Chevrolet Traverse (L, LS, LT, RS, Premier, High Country), with repair costs ranging from $150 to $900.
Common Causes
Typical Repair Cost
Based on 1 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.
Diagnostic Tools
P16A7 does not use the standard P/B/C/U prefix. It may be a manufacturer-specific code, so verify that a scanner supports your exact year, model and module before buying.
FAQ
What does P16A7 mean?
P16A7 stands for "Engine Controls Ignition Relay Feedback Circuit 2." A General Motors manufacturer-specific code (Chevrolet, GMC, Buick, Cadillac). The ECM receives three ignition-voltage feeds: two supplied by the engine controls ignition relay and one by the ignition main relay. It continuously compares the two monitored ignition-voltage circuits and sets P16A7 when the difference exceeds 3 volts for more than about 1 second. Because the ECM's own power supply is in question, symptoms range from a check engine light with no drivability complaint to hard starting, stalling, or a no-start. Note that P16A7 is manufacturer-specific — on non-GM vehicles the same code number carries a different definition, so confirm the make before diagnosing.
What are the most common causes of P16A7?
The most common causes of P16A7 are: Failed engine controls ignition relay, Open or shorted wiring in the ignition feed circuits to the ECM, Poor electrical connection — corroded, loose, or backed-out terminals in the underhood fuse/relay box, Blown fuse or poor ground in the ignition voltage supply, Water intrusion or corrosion in the fuse block, Failed ECM (rare — verify power and grounds first). The specific cause varies by vehicle.
How much does it cost to fix P16A7?
Repair costs for P16A7 range from $150 to $900, depending on the vehicle and root cause.
Which vehicles are affected by P16A7?
Au7o has documented P16A7 across 1 vehicle models from 1 manufacturers: Chevrolet.
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.