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 ECM/PCM.
NO - Go to step 4.
- Turn the ignition switch OFF.
- Remove the throttle actuator control module relay (A).
- Test the throttle actuator control module relay (see
POWER RELAY TEST
).
Is the relay OK?
YES - Go to step 7.
NO - Replace the throttle actuator control module relay, then go to step 10.
- Jump the SCS line with the HDS.
- Disconnect ECM/PCM connector D (17P).
- Check for continuity between ECM/PCM connector terminal D15 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 ECM/PCM (D15), then go to step 10.
NO - Go to step 17.
- Reconnect all connectors.
- Turn the ignition switch ON (II).
- Reset the ECM/PCM with the HDS.
- Do the ECM/PCM idle learn procedure (see ECM/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 relay, the throttle actuator control module, and the ECM/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 ECM/PCM if it does not have the latest software (see UPDATING THE ECM/PCM ), or substitute a known-good ECM/PCM (see SUBSTITUTING THE ECM/PCM ).
- Check for Temporary DTCs or DTCs with the HDS.
Is DTC P2252 indicated?
YES - Check for poor connections or loose terminals at the throttle actuator control module relay, the throttle actuator control module, and the ECM/PCM. If the ECM/PCM was updated, substitute a known-good ECM/PCM (see SUBSTITUTING THE ECM/PCM ), then recheck. If the ECM/PCM was substituted, go to step 1.
NO - If the ECM/PCM was updated, troubleshooting is complete. If the ECM/PCM was substituted, replace the original ECM/PCM (see ECM/PCM REPLACEMENT ). If any other Temporary DTCs or DTCs are indicated, go to the indicated DTCs troubleshooting.
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.
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.
Rather have a pro handle this?
A certified mobile mechanic comes to your home or office. They bring the tools, you stay comfortable. No tow truck, no waiting room, no surprises.
No obligation. See pricing before you book.