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General Troubleshooting Information

General Troubleshooting Information

Intermittent Failures
The term "intermittent failure" means a system may have had a failure, but it checks OK now. If the Malfunction Indicator Lamp (MIL) on the dash does not come on, check for poor connections or loose terminals at all connectors related to the circuit that you are troubleshooting.

Opens and Shorts
"Open" and "Short" are common electrical terms. An open is a break in a wire or at a connection. A short is an accidental connection of a wire to ground or to another wire. In simple electronics, this usually means something won't work at all. With complex electronics (such as ECMs) this can sometimes mean something works, but not the way it's supposed to.

How to Use the PGM Tester or a Scan Tool

If the MIL (Malfunction Indicator Lamp) has come on




1. Start the engine and check the MIL (A).

NOTE: If the ignition switch is turned ON (II), and the engine is not started, the MIL will stay on for 15 - 20 seconds.




2. If the MIL stays on, connect the Honda PGM Tester (A) or an OBD II scan tool to the Data Link Connector (DLC) (B) located under the driver's side of the dashboard.
3. Turn the ignition switch ON (II).
4. Check the Diagnostic Trouble Code (DTC) and note it. Also check the freeze data. Refer to the DTC Troubleshooting Index, and begin the appropriate troubleshooting procedure.
5. If you do not find any DTCs, go to MIL circuit troubleshooting.

NOTE:
- Freeze data indicates the engine conditions when the first malfunction, misfire, or fuel trim malfunction was detected.
- The scan tool and the Honda PGM Tester can read the DTC, freeze data, current data, and other Engine Control Module (ECM) data.
- For specific operations, refer to the user's manual that came with the scan tool or Honda PGM Tester.

If the MIL did not stay
If the MIL did not come on but there is a driveability problem, refer to the Symptom Troubleshooting Index in this section.

If you can't duplicate the DTC
Some of the troubleshooting in this section requires you to reset the ECM and try to duplicate the DTC. If the problem is intermittent and you can't duplicate the code, do not continue through the procedure. To do so will only result in confusion and, possibly, a needlessly replaced ECM.




How to Reset the ECM
You can reset the ECM in either of two ways:
- Use the OBD II scan tool or Honda PGM Tester to reset the ECM memory.
See the OBD II scan tool or Honda PGM Tester user's manuals for specific instructions.
- Turn the ignition switch OFF, and remove the No.6 ECU (ECM) (15 A) fuse (A) from the under-hood fuel relay box (B) for 10 seconds.

How to End a Troubleshooting Session
(required after any troubleshooting)
1. Reset the ECM as described above.
2. Do the ECM idle learn procedure.
3. Turn the ignition switch OFF.
4. Disconnect the OBD II scan tool or Honda PGM Tester from the DLC.

NOTE: The ECM is part of the immobilizer system. If you replace the ECM, it will have a different immobilizer code. In order for the engine to start, you must rewrite the immobilizer code with the Honda PGM Tester.

How to Remove the ECM for Testing
1. Remove the passenger's dashboard lower cover, the passenger's kick panel, and the glove box.




2. Remove the ECM mounting bolts (B) and the ECM (C).
3. Remove the ECM (B).
4. Install the ECM in the reverse order of removal.

How to Troubleshoot Circuits at the ECM

Special Tools Required
- Digital Multimeter KS-AHM-32-003 (1) or a commercially available digital multimeter
- Backprobe Set 07SAZ-001000A (2)




1. Connect the back probe adapters (A) to the stacking patch cords (B), and connect the cords to a digital multimeter (C).
2. Using the wire insulation as a guide for the contoured tip of the back probe adapter, gently slide the tip into the connector from the wire side until it touches the end of the wire terminal.




3. If you cannot get to the wire side of the connector or the wire side is sealed (A), disconnect the connector and probe the terminals (B) from the terminal side. Do not force the probe into the connector.

NOTE: Do not puncture the insulation on a wire. Punctures can cause poor or intermittent electrical connections.

ECM Updating and Substitution for Testing

Special Tools Required
Honda Interface Module (HIM)

Use this procedure when you have to substitute a known-good ECM in a troubleshooting procedure. Update the ECM only if the ECM does not already have the latest software loaded.

NOTE:
- Make sure the battery is fully charged before you update the ECM.
- To prevent ECM damage during the update, do not turn the ignition switch OFF, and do not use any of the vehicle's electrical devices (light, horn, radio, etc.)




How to Update the ECM
1. Turn the ignition switch ON (II). Do not start the engine.
2. Connect the Honda Interface Module (HIM) to the Data Link Connector (DLC) (A) located under the driver's side of dashboard.
3. Do the ECM update procedure as described on the HIM label and in the ECM update system.

How to Substitute the ECM
1. Remove the ECM from the vehicle.
2. Install a known-good ECM in the vehicle.
3. Rewrite the immobilizer code with the ECM replacement procedure from the Honda PGM Tester. It allows you to start the engine.
4. After completing your tests, reinstall the original ECM and rewrite the immobilizer code with the ECM replacement procedure on the Honda PGM Tester again.
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