Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
DTC P2552: Throttle Actuator Control Module Relay Malfunction
- Turn the ignition switch ON (II).
- Clear the DTC with the HDS.
- Do the ETCS TEST in the INSPECTION MENU with the HDS.
Is the RELAY circuit OK?
YES - Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the throttle actuator control module relay, the throttle actuator control module, and the PCM.
NO - Go to step 4.
- Turn the ignition switch OFF.
- Jump the SCS line with the HDS.
- Remove the throttle actuator control module relay (A).
- Disconnect PCM connector E (31P).
- Check for continuity between PCM connector terminal E3 and body ground.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES - Repair short in the wire between the throttle actuator control module relay and the PCM (E3), then go to step 10.
NO - Go to step 9.
- Test the throttle actuator control module relay (see
POWER RELAY TEST
).
Is the relay OK?
YES - Go to step 17.
NO - Replace the throttle actuator control module relay, then go to step 10.
- Reconnect PCM connector E (31P).
- Turn the ignition switch ON (II).
- Reset the PCM with the HDS.
- Do the PCM idle learn procedure (see PCM IDLE LEARN PROCEDURE ).
- Turn the ignition switch OFF.
- Turn the ignition switch ON (II), and wait 10 seconds.
- Check for Temporary DTCs or DTCs with the HDS.
Is DTC P2552 indicated?
YES - Check for poor connections or loose terminals at the throttle actuator control module, the throttle actuator control module relay, and the PCM, then go to step 1.
NO - Troubleshooting is complete. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTCs troubleshooting.
- Reconnect all connectors.
- Update the PCM if it does not have the latest software (see UPDATING THE PCM ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ).
- Check for Temporary DTCs or DTCs with the HDS.
Is DTC P2552 indicated?
YES - Check for poor connections or loose terminals at the throttle actuator control module, the throttle actuator control module relay, and the PCM. If the PCM was updated, substitute a known-good PCM (see SUBSTITUTING THE PCM ), then recheck. If the PCM was substituted, go to step 1.
NO - If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM (see PCM REPLACEMENT ). If any other Temporary DTCs or DTCs are indicated, go to the indicated DTCs troubleshooting.
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.