F-CAN Circuit Troubleshooting
- Turn the ignition switch to LOCK (0).
- Jump the SCS line with the HDS.
- Disconnect PCM connector A (49P).
- Measure the resistance between PCM connector terminals A48 and A49.
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Is there about 85-103 Ω (with VTM-4), or 88-107 Ω (without VTM-4)?
YES -Go to step 19.
NO -Go to step 5.
- Disconnect these connectors:
- Gauge control module 32P (see GAUGE CONTROL MODULE REPLACEMENT ).
- VSA modulator-control unit 36P (see VSA MODULATOR-CONTROL UNIT REMOVAL AND INSTALLATION ).
- Engine mount control unit 16P (see ENGINE MOUNT CONTROL UNIT REPLACEMENT ).
- Yaw rate-acceleration sensor 5P (see YAW RATE-ACCELERATION SENSOR REPLACEMENT ).
- SRS unit A (39P) (see SRS UNIT REPLACEMENT ).
- VTM-4 control unit A (22P) (with VTM-4) (see VTM-4 CONTROL UNIT REPLACEMENT ).
- TPMS control unit 20P (see TPMS CONTROL UNIT REPLACEMENT ).
- Check for continuity between PCM connector terminals A48 and A49.
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Is there continuity?
YES -Repair a short in the wire between PCM connector terminals A48 and A49.
NO -Go to step 7.
- Check for continuity between PCM connector terminal A48 and gauge control module 32P connector terminal No. 30.Fig 3: Checking Continuity Between PCM Connector Terminal A48 And Gauge Control Module 32P Connector Terminal No. 30
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Is there continuity?
YES -Go to step 8.
NO -Repair an open in the wire between the PCM (A48) and the gauge control module.
- Check for continuity between PCM connector terminal A48 and VSA modulator-control unit 36P connector terminal No. 14.Fig 4: Checking Continuity Between PCM Connector Terminal A48 And VSA Modulator-Control Unit 36P Connector Terminal No. 14
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Is there continuity?
YES -Go to step 9.
NO -Repair an open in the wire between the PCM (A48) and the VSA modulator-control unit.
- Check for continuity between PCM connector terminal A48 and engine mount control unit 16P connector terminal No. 14.Fig 5: Checking Continuity Between PCM Connector Terminal A48 And Engine Mount Control Unit 16P Connector Terminal No. 14
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Is there continuity?
YES -
- With VTM-4: Go to step 10.
- Without VTM-4: Go to step 11.
NO -Repair an open in the wire between the PCM (A48) and the engine mount control unit.
- Check for continuity between PCM connector terminal A48 and VTM-4 control unit connector A (22P) terminal No. 11.Fig 6: Checking Continuity Between PCM Connector Terminal A48 And VTM-4 Control Unit Connector A (22P) Terminal No. 11
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES -Go to step 11.
NO -Repair an open in the wire between the PCM (A48) and the VTM-4 control unit.
- Check for continuity between PCM connector terminal A49 and gauge control module 32P connector terminal No. 29.Fig 7: Checking Continuity Between PCM Connector Terminal A49 And Gauge Control Module 32P Connector Terminal No. 29
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES -Go to step 12.
NO -Repair an open in the wire between the PCM (A49) and the gauge control module.
- Check for continuity between PCM connector terminal A49 and VSA modulator-control unit 36P connector terminal No. 1.Fig 8: Checking Continuity Between PCM Connector Terminal A49 And VSA Modulator-Control Unit 36P Connector Terminal No. 1
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES -Go to step 13.
NO -Repair an open in the wire between the PCM (A49) and the VSA modulator-control unit.
- Check for continuity between PCM connector terminal A49 and engine mount control unit 16P connector terminal No. 12.Fig 9: Checking Continuity Between PCM Connector Terminal A49 And Engine Mount Control Unit 16P Connector Terminal No. 12
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES -
- With VTM-4: Go to step 14.
- Without VTM-4: Go to step 17.
NO -Repair an open in the wire between the PCM (A49) and the engine mount control unit.
- Check for continuity between PCM connector terminal A49 and VTM-4 control unit connector A (22P) terminal No. 22.Fig 10: Checking Continuity Between PCM Connector Terminal A49 And VTM-4 Control Unit Connector A (22P) Terminal No. 22
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES -Go to step 15.
NO -Repair an open in the wire between the PCM (A49) and the VTM-4 control unit.
- Reconnect the VTM-4 control unit A (22P) connector.
- Measure the resistance between PCM connector terminals A48 and A49.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there about 108-132 Ω?
YES -Go to step 19.
NO -Substitute a known-good VTM-4 control unit (see VTM-4 CONTROL UNIT REPLACEMENT ), then reconnect PCM connector A. If the HDS identifies the vehicle, replace the original VTM-4 control unit (see VTM-4 CONTROL UNIT REPLACEMENT ).
- Reconnect the VSA modulator-control unit 36P connector.
- Measure the resistance between PCM connector terminals A48 and A49.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there about 108-132 Ω?
YES -Go to step 19.
NO -Substitute a known-good VSA modulator-control unit (see VSA MODULATOR-CONTROL UNIT REMOVAL AND INSTALLATION ), then reconnect PCM connector A. If the HDS identifies the vehicle, replace the original VSA modulator-control unit (see VSA MODULATOR-CONTROL UNIT REMOVAL AND INSTALLATION ).
- Disconnect these connectors:
- Gauge control module 32P (see GAUGE CONTROL MODULE REPLACEMENT ).
- VSA modulator-control unit 36P (see VSA MODULATOR-CONTROL UNIT REMOVAL AND INSTALLATION ).
- Engine mount control unit 16P (see ENGINE MOUNT CONTROL UNIT REPLACEMENT ).
- Yaw rate-acceleration sensor 5P (see YAW RATE-ACCELERATION SENSOR REPLACEMENT ).
- SRS unit A (39P) (see SRS UNIT REPLACEMENT ).
- VTM-4 control unit A (22P) (with VTM-4) (see VTM-4 CONTROL UNIT REPLACEMENT ).
- TPMS control unit 20P (see TPMS CONTROL UNIT REPLACEMENT ).
- Check for continuity between PCM connector terminal A48 and body ground.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES -Repair a short in the wire between the PCM (A48) and the gauge control module, the VSA modulator-control unit, the engine mount control unit, the yaw rate-acceleration sensor, the SRS unit, the VTM-4 control unit, the TPMS control unit, or the DLC.
NO -Go to step 21.
- Check for continuity between PCM connector terminal A49 and body ground.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES -Repair a short in the wire between the PCM (A49) and the gauge control module, the VSA modulator-control unit, the engine mount control unit, the yaw rate-acceleration sensor, the SRS unit, the VTM-4 control unit, the TPMS control unit, or the DLC.
NO -Go to step 22.
- Reconnect all connectors.
- Connect the HDS to the DLC (see HOW TO USE THE HDS (HONDA DIAGNOSTIC SYSTEM) ).
- Disconnect the gauge control module 32P connector.
- Turn the ignition switch to ON (II), and read the HDS.
Does the HDS identify the vehicle?
YES -Replace the gauge control module (see GAUGE CONTROL MODULE REPLACEMENT ).
NO -Go to step 26.
- Turn the ignition switch to LOCK (0).
- Reconnect the gauge control module 32P connector.
- Disconnect the VSA modulator-control unit 36P connector.
- Turn the ignition switch to ON (II), and read the HDS.
Does the HDS identify the vehicle?
YES -Replace the VSA control unit (see VSA MODULATOR-CONTROL UNIT REMOVAL AND INSTALLATION ).
NO -Go to step 30.
- Turn the ignition switch to LOCK (0).
- Reconnect the VSA modulator-control unit 36P connector.
- Disconnect the engine mount control unit 16P connector.
- Turn the ignition switch to ON (II), and read the HDS.
Does the HDS identify the vehicle?
YES -Replace the engine mount control unit (see ENGINE MOUNT CONTROL UNIT REPLACEMENT ).
NO -Go to step 34.
- Turn the ignition switch to LOCK (0).
- Reconnect the engine mount control unit 16P connector.
- Disconnect the yaw rate-acceleration sensor 5P connector.
- Turn the ignition switch to ON (II), and read the HDS.
Does the HDS identify the vehicle?
YES -Replace the yaw rate-acceleration sensor (see YAW RATE-ACCELERATION SENSOR REPLACEMENT ).
NO -Go to step 38.
- Turn the ignition switch to LOCK (0).
- Reconnect the yaw rate-acceleration sensor 5P connector.
- Disconnect SRS unit connector A (39P).
- Turn the ignition switch to ON (II), and read the HDS.
Does the HDS identify the vehicle?
YES -Replace the SRS unit (see SRS UNIT REPLACEMENT ).
NO -
- With VTM-4: Go to step 42.
- Without VTM-4: Go to step 46.
- Turn the ignition switch to LOCK (0).
- Reconnect SRS unit connector A (39P).
- Disconnect the VTM-4 control unit A (22P) connector.
- Turn the ignition switch to ON (II), and read the HDS.
Does the HDS identify the vehicle?
YES -Replace the VTM-4 control unit (see VTM-4 CONTROL UNIT REPLACEMENT ).
NO -Go to step 46.
- Turn the ignition switch to LOCK (0).
- Without VTM-4: Reconnect SRS unit connector A (39P).
- With VTM-4: Disconnect the VTM-4 control unit A (22P) connector.
- Disconnect the TPMS control unit 20P connector.
- Turn the ignition switch to ON (II), and read the HDS.
Does the HDS identify the vehicle?
YES -Replace the TPMS control unit (see TPMS CONTROL UNIT REPLACEMENT ).
NO -Update the PCM if it does not have the latest software (see PCM UPDATE ), or substitute a known-good PCM (see SUBSTITUTING THE PCM ), then recheck. If the HDS identifies the vehicle with a known-good PCM, replace the original PCM (see PCM REPLACEMENT ).