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HOMESERVICE MANUALSHONDA2002CIVIC SIREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 188 (POWER TAILGATE)DTC TROUBLESHOOTINGDTC B1390: POWER TAILGATE CLOSER FUNCTION ERROR

2002 Honda Civic Si

DTC B1390: Power Tailgate Closer Function Error

2002 Honda Civic SiSECTION DTC B1390: Power Tailgate Closer Function Error

WARNING: This page is about a different car, the 2006 Honda Odyssey and 2005 Honda Odyssey. However, it is still accessible from the selected car via links, so may be relevant.

With the tailgate closed, pull the tailgate outside handle and wait for 10 seconds.
Turn the ignition switch OFF, and then back ON (II).
Clear the DTCs with the HDS.
Listen for the sound of the latch releasing.
Is there sound?
1. YES - Go to step 5.
2. NO - Go to step 13.
Check for DTCs with the HDS.
Is DTC B1390 indicated?
1. YES - Go to step 6.
2. NO - Intermittent failure. The power tailgate system is OK at this time. Check for loose or poor connections at the power tailgate control unit connector, and at the closer motor connector.
Check for DTCs with the HDS.
Are DTC B1380, B1381, B1382, B1383, and/or B1384 also indicated?
1. YES - Troubleshoot the indicated DTCs.
2. NO - Go to step 7.
Turn the ignition switch OFF.
Open the tailgate.
Disconnect the 14P connector from the power tailgate control unit.
Check for continuity between the power tailgate control unit connector C (14P) No. 1 and No. 11 terminals, and No. 2 and No. 11 terminals.

Fig 1: Checking Continuity Between Power Tailgate Control Unit Connector C (14P) Terminals 1 & 11 And 2 & 11 Terminals
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES - Replace the power tailgate control unit.
2. NO - Go to step 11.
Disconnect the 6P connector from the tailgate closer unit.
At the tailgate closer unit side, check for continuity between the No. 1 and No. 2 terminals, and No. 1 and No. 3 terminals.

Fig 2: Checking Continuity Between Terminals 1 & 2 And 1 & 3 Terminals
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES - Repair an open in the wire between the tailgate closer unit and the power tailgate control unit 14P connector.
2. NO - Replace the tailgate closer unit.
Turn the ignition switch OFF.
Open the tailgate.
Disconnect the 2P connector from the tailgate closer motor.
Disconnect the 20P connector from the power tailgate control unit.
Check for continuity between the power tailgate control unit connector B (20P) No. 1 and No. 2 terminals and the tailgate closer motor 2P connector No. 1 and No. 2 terminals.

Fig 3: Checking Continuity Between Control Unit Connector B (20P) Terminals 1 & 2 And Tailgate Closer Motor 2P Connector Terminals 1 & 2
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES - Go to step 18.
2. NO - Repair an open in the wire.
Measure voltage between the power tailgate control unit connector B (20P) No. 12 terminal and body ground.

Fig 4: Measuring Voltage Between Power Tailgate Control Unit Connector B (20P) Terminal 12 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?
1. YES - Go to step 19.
2. NO - Check for No. 17 (20 A) fuse in the driver's under-dash fuse/relay box. If the fuse is OK, check for an open in the wire between the driver's under-dash fuse/relay box and power tailgate control unit.
Check for continuity between the power tailgate control unit connector A (5P) No. 4 terminal and body ground.

Fig 5: Checking Continuity Between Power Tailgate Control Unit Connector A (5P) Terminal 4 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES - Go to step 20.
2. NO - Repair an open in the wire or poor ground (G701).
Turn the tailgate lock latch to the fully-closed position using a screwdriver.
Reconnect the tailgate closer motor 2P connector.
Using jumper wires, connect battery power to the power tailgate control unit connector B (20P) No. 2 (or No. 1) terminal and ground the No. 1 (or No. 2) terminal momentarily.

Fig 6: Connecting Battery Power To Power Tailgate Control Unit Connector B (20P) Terminal 2 And Ground Terminal 1 (Using Jumper Wires)
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Does the motor run smoothly?
1. YES - Replace the power tailgate control unit.
2. NO - Go to step 23.
Reconnect the 6P connector to the tailgate closer unit.
Check for continuity between the power tailgate control unit connector B (20P) No. 1 and No. 2 terminals and body ground.

Fig 7: Checking Continuity Between Power Tailgate Control Unit Connector B (20P) Terminals 1 & 2 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES - Go to step 25.
2. NO - Go to step 27.
Disconnect the 6P connector from the tailgate closer unit.
Check for continuity between the power tailgate control unit connector B (20P) No. 1 and No. 2 terminals and body ground.

Fig 8: Checking Continuity Between Power Tailgate Control Unit Connector B (20P) Terminals 1 & 2 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES - Repair a short in the wire.
2. NO - Replace the tailgate closer unit.
Check for continuity between the power tailgate control unit connector B (20P) No. 9 terminal and body ground.

Fig 9: Checking Continuity Between Power Tailgate Control Unit Connector B (20P) Terminal 9 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES - Repair a short in the wire.
2. NO - Check for No. 17 (20 A) fuse in the driver's under-dash fuse/relay box. If the fuse is OK, check for an open in the wire between the driver's under-dash fuse/relay box and power tailgate control unit.