Code 54 Cruze

The relay itself is a small, replaceable box in the under-hood fuse box (often called the underhood fuse block). Over time, relay contacts corrode, burn, or stick open, causing low voltage to the ECM’s sense circuit. This is the cheapest and easiest fix.

Cold Start Exhaust Gas Temperature Sensor Circuit High / Open (Bank 1 Sensor 2). code 54 cruze

In an emergency, you can temporarily bypass the relay circuit to get home. The relay itself is a small, replaceable box

Connect your scanner. Confirm the code is P054A. Look for "Pending" codes as well. If you have multiple codes (e.g., P054A combined with a P0137 Oxygen Sensor code), it strongly suggests a wiring issue affecting multiple sensors rather than just one bad part. Cold Start Exhaust Gas Temperature Sensor Circuit High

Disconnect the fuel pump harness connector (under the rear seat cushion on sedans, or under the car near the tank). Measure resistance between the pump power wire and ground. Open circuit indicates a failed pump, but Code 54 is rarely the pump itself. If resistance is within spec (2-5 ohms), the pump motor is likely fine—suspect wiring or relay.