DTC P0404: EGR Control Circuit Range/Performance Problem
- Turn the ignition switch ON (II).
- Clean the DTC with the HDS.
- Start the engine. Hold the engine speed at 3,000 RPM without load (in Park or neutral) until the radiator fan comes on, then let it idle.
- Do the EGR TEST in the INSPECTION MENU with the HDS.
Is the test result OK?
YES - Intermittent failure, system is OK at this time. Clean any carbon build-up on the EGR valve with carburetor cleaner.
NO - Go to step 5.
- Turn the ignition switch OFF.
- Disconnect the EGR valve 6P connector.
- At the sensor side, measure resistance between EGR valve 6P connector terminals No. 1 and No. 2.
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Is there 100 kΩ or more?
YES - Go to step 25.
NO - Go to step 8.
- Measure resistance between EGR valve 6P connector terminals No. 1 and No. 3.
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Is there 100 kΩ or more?
YES - Go to step 25.
NO - Go to step 9.
- Check for continuity between EGR valve 6P connector terminal No. 6 and body ground.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES - Go to step 10.
NO - Repair open in the wire between the EGR valve and G101, then go to step 26.
- Jump the SCS line with the HDS.
- Disconnect PCM connector C (44P).
- Check for continuity between PCM connector terminal C9 and body ground.
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Is there continuity?
YES - Repair short in the wire between the PCM (C9) and the EGR valve, then go to step 26.
NO - Go to step 13.
- Check for continuity between PCM connector terminal C9 and EGR valve 6P connector terminal No. 4.Fig 5: Checking Continuity Between PCM Connector Terminal C9 And EGR Valve 6P Connector Terminal No. 4
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES - Go to step 14.
NO - Repair open in the wire between the PCM (C9) and the EGR valve, then go to step 26.
- Remove the EGR valve (see EGR VALVE REPLACEMENT ).
- Clean the intake manifold EGR port with carburetor cleaner. Also, clean the passage inside the EGR valve with carburetor cleaner.
- Install the EGR valve (see EGR VALVE REPLACEMENT ).
- Reconnect the EGR valve 6P connector.
- Reconnect PCM connector C (44P).
- Turn the ignition switch ON (II).
- Reset the PCM with the HDS.
- Do the PCM idle learn procedure (see PCM IDLE LEARN PROCEDURE ).
- Start the engine. Hold the engine speed at 3,000 RPM without load (in Park or neutral) until the radiator fan comes on, then let it idle.
- Do the EGR TEST in the INSPECTION MENU with the HDS.
Is the result OK?
YES - Go to step 32.
NO - Go to step 24.
- Turn the ignition switch OFF.
- Replace the EGR valve (see EGR VALVE REPLACEMENT ).
- Reconnect all connectors.
- Turn the ignition switch ON (II).
- Reset the PCM with the HDS.
- Do the PCM idle learn procedure (see PCM IDLE LEARN PROCEDURE ).
- Start the engine. Hold the engine speed at 3,000 RPM without load (in Park or neutral) until the radiator fan comes on, then let it idle.
- Do the EGR TEST in the INSPECTION MENU with the HDS.
- Check for Temporary DTCs or DTCs with the HDS.
Are any Temporary DTCs or DTCs indicated?
YES - If DTC P0404 is indicated, check for poor connections or loose terminals at the EGR valve and the PCM. If the connections and terminals are OK, go to step 34. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC'S TROUBLESHOOTING .
NO - Go to step 33.
- Monitor the OBD STATUS for DTC P0404 in the DTCs MENU with the HDS.
Does the screen indicate PASSED?
YES - Troubleshooting is complete.
NO - If the screen indicates FAILED, go to step 1 and recheck. If the screen indicates EXECUTING, keep driving until a result comes on. If the screen indicates OUT OF CONDITION, go to step 30 and recheck.
- Update the PCM if it does not have the latest software, or substitute a know-good PCM (see PCM UPDATING AND SUBSTITUTION FOR TESTING ).
- Do the EGR TEST in the INSPECTION MENU with the HDS.
- Check for Temporary DTCs or DTCs with the HDS.
Are any Temporary DTCs or DTCs indicated?
YES - If DTC P0404 is indicated, check for poor connections or loose terminals at the EGR valve and the PCM, then go to step 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC'S TROUBLESHOOTING .
NO - If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM (see PCM REPLACEMENT ).