Key Interlock System Circuit Troubleshooting

Fig 1: Key Interlock System Circuit Troubleshooting Workflow Chart

Courtesy of AMERICAN HONDA MOTOR CO., INC.

NOTE:

SRS COMPONENTS ARE LOCATED IN THIS AREA. REVIEW THE SRS COMPONENT LOCATIONS , and PRECAUTIONS AND PROCEDURES before doing repairs or servicing.
Refer to the Electrical Wiring Diagrams for the location of the under-dash fuse/relay box connectors.

DTC check:

1. Check the A/T system DTCs with the HDS.

DTC Description	Confirmed DTC	Pending DTC

Are DTCs indicated?

YES : Go to DTC troubleshooting.

NO : Go to step 2.

Key interlock system check:

1. Check the A/T system DATA LIST with the HDS.

Signal	Current conditions
Signal	Values	Unit
ATP-P Switch
Park Pin Switch

Are the ATP-P and Park Pin Switch indicating when the shift lever is in P, and does the transmission range switch indicate OFF when the shift lever is shifted to any position other than P?

YES : Go to step 3.

NO : ATP-P switch troubleshooting 10.

NO : Park pin switch troubleshooting 7.

Determine possible failure area (steering lock, others):
- 1. Move the shift lever to P and set the parking brake.
- 2. Remove the steering column covers.
- 3. Disconnect the following connector.
  Steering lock 7P connector
- 4. Turn the ignition switch to ACCESSORY (I).
- 5. Check if the ignition switch can be turned to LOCK (0).
Can the ignition switch be turned to LOCK (0)?

YES : Go to step 4.

NO : Faulty key interlock solenoid; REPLACE THE STEERING LOCK .
Fuse check:
- 1. Check the following fuse.
  Fuse No. B20 (7.5 A)
  
  Location Under-dash fuse/relay box
Is the fuse OK?

YES : Go to step 5.

NO : Replace the fuse. If the fuse blows again, repair a short to ground in the No. B20 (7.5 A) fuse circuit.
Shorted wire check (KEY SOL line):
- 1. Make sure the ignition switch is turned to LOCK (0).
- 2. Disconnect the following connector.
  Under-dash fuse/relay box connector P (20P)
- 3. Check for continuity between test points 1 and 2.
  Test condition IG LOCK (0)
  
  Steering lock 7P connector: disconnected
  
  Under-dash fuse/relay box connector P (20P): disconnected
  
  Test circuit KEY SOL
  
  Test point 1 Steering lock 7P connector No. 4 (PUR)
  
  Test point 2 Body ground
  
  Fig 2: Checking Continuity Between Steering Lock 7P Connector No. 4 (PUR) And Body Ground
  Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?

YES : Repair a short to body ground in the wire.

NO : The KEY SOL wire is OK. Go to step 6.
Open wire check (KEY SOL line):
- 1. Check for continuity between test points 1 and 2.
  Test condition IG LOCK (0)
  
  Steering lock 7P connector: disconnected
  
  Under-dash fuse/relay box connector P (20P): disconnected
  
  Test circuit KEY SOL
  
  Test point 1 Under-dash fuse/relay box connector P (20P) No. 10 (PUR)
  
  Test point 2 Steering lock 7P connector No. 4 (PUR)
  
  Fig 3: Checking Continuity Between Under-Dash Fuse/Relay Box Connector P (20P) No. 10 (PUR) And Steering Lock 7P Connector No. 4 (PUR)
  Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?

YES : The KEY SOL wire is OK. Go to step 7.

NO : Repair an open or high resistance in the wire.
Park pin switch check:
- 1. Remove the center console.
- 2. Disconnect the following connectors.
  Select lever 12P connector
- 3. DO THE PARK PIN SWITCH TEST .
Is switch OK?

YES : Go to step 8.

NO : REPLACE THE PARK PIN SWITCH .
Shorted wire check (P-PIN SW line):
- 1. Check for continuity between test points 1 and 2.
  Test condition IG LOCK (0)
  
  Steering lock 7P connector: disconnected
  
  Under-dash fuse/relay box connector P (20P): disconnected
  
  Select lever 12P connector: disconnected
  
  Test circuit P-PIN SW
  
  Test point 1 Select lever 12P connector No. 6 (LT BLU)
  
  Test point 2 Body ground
  
  Fig 4: Checking Continuity Between Select Lever 12P Connector No. 6 (LT BLU) And Body Ground
  Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?

YES : Repair a short to body ground in the wire.

NO : The P-PIN SW wire is OK. Go to step 9.
Open wire check (GND line) 1:
- 1. Check for continuity between test points 1 and 2.
  Test condition IG LOCK (0)
  
  Steering lock 7P connector: disconnected
  
  Under-dash fuse/relay box connector P (20P): disconnected
  
  Select lever 12P connector: disconnected
  
  Test circuit GND
  
  Test point 1 Select lever 12P connector No. 5 (BLK)
  
  Test point 2 Body ground
  
  Fig 5: Checking Continuity Between Select Lever 12P Connector No. 5 (BLK) And Body Ground
  Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?

YES : The GND wire is OK. Go to step 10.

NO : Repair an open or high resistance in the wire.
Transmission range switch check:
- 1. DO THE TRANSMISSION RANGE SWITCH TEST .
Is switch OK?

YES : Go to step 11.

NO : REPLACE THE TRANSMISSION RANGE SWITCH .
Open wire check (ATP-P line):
- 1. Disconnect the following connectors.
  Under-dash fuse/relay box connector D (32P)
  
  Transmission range switch 10P connector
- 2. Check for continuity between test points 1 and 2.
  Test condition IG LOCK (0)
  
  Steering lock 7P connector: disconnected
  
  Under-dash fuse/relay box connector P (20P): disconnected
  
  Select lever 12P connector: disconnected
  
  Under-dash fuse/relay box connector D (32P): disconnected
  
  Transmission range switch 10P connector: disconnected
  
  Test circuit ATP-P
  
  Test point 1 Under-dash fuse/relay box connector D (32P) No. 22 (YEL)
  
  Test point 2 Transmission range switch 10P connector No. 10 (BLK/BLU)
  
  Fig 6: Checking Continuity Between Under-Dash Fuse/Relay Box Connector D (32P) No. 22 (YEL) And Transmission Range Switch 10P Connector No. 10 (BLK/BLU)
  Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?

YES : The ATP-P wire is OK. Go to step 12.

NO : Repair an open or high resistance in the wire.
Open wire check (GND line) 2:
- 1. Check for continuity between test points 1 and 2.
  Test condition IG LOCK (0)
  
  Steering lock 7P connector: disconnected
  
  Under-dash fuse/relay box connector P (20P): disconnected
  
  Select lever 12P connector: disconnected
  
  Under-dash fuse/relay box connector D (32P): disconnected
  
  Transmission range switch 10P connector: disconnected
  
  Test circuit GND
  
  Test point 1 Transmission range switch 10P connector No. 6 (BLK)
  
  Test point 2 Body ground
  
  Fig 7: Checking Continuity Between Transmission Range Switch 10P Connector No. 6 (BLK) And Body Ground
  Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?

YES : The GND wire is OK. Faulty MICU; REPLACE THE UNDER-DASH FUSE/RELAY BOX .

NO : Repair an open or high resistance in the wire.