What the P0655 code means?

The P0655 is an OBD-II generic code which indicates that the circuitry meant to relay a pending engine overheats is experiencing a voltage-related malfunction. Typically, it means that there is a problem in the circuitry that operates this system.

What causes the P0655 code?

The most common cause of this code being stored comes from defects in system circuitry. Loose, broken, or corroded wiring and electrical connectors are common and should be investigated first. Other possible causes include a defective PCM, faulty engine over temp indicator bulb, or bad engine temperature sensor. If there are other codes related to engine temperature, that were stored prior to this code being stored, diagnose and repair those before attempting to diagnose this code. Freeze frame data can be useful when diagnosing this code.

What are the symptoms of the P0655 code?

1. Engine drivability issues.

2. Inoperative engine hot lamp.

3. Engine hot lamp is illuminated constantly.

Common mistakes when diagnosing the P0655 code:

Technicians report that the engine coolant temperature sensor is often replaced in error when the PCM
driver is at fault.

How serious is the P0655 code?

The P0655 code will not prevent the car from starting, but it can be that the vehicle has a faulty sensor that
could easily lead to an overheating issue.

What repairs can fix the P0655 code?

1. Checking the code with a scanner, resetting and doing a road test to see if the P0655 code returns.

2. Visually inspecting all electrical connections, the PCM and the engine wiring harness. Any damaged,
disconnected or corroded components, wires, or connectors will be repaired and reinstalled.

3. Though individual control modules rarely fail, they will be tested according to manufacturer's specs and replaced if needed. The PCM is then reprogrammed.