DTC C1921: Parking Position Switch Circuit
DTC detecting condition:
- A fault is detected if the switch was positioned at lock or release continuously for 90 seconds while the vehicle is stopped.
- A fault is detected if an irregular switch condition continues for a predetermined period of time immediately after the switch position is changed. A fault is also detected if the switch condition is not confirmed afterwards.
- A fault is detected if the switch harness is open or shorted.
Trouble symptom:
- AVH does not function. (Models with EyeSight)
- Parking brake system does not operate.
Wiring diagram:
Parking brake/brake fluid level warning light system Refer to WIRING SYSTEM>PARKING BRAKE/BRAKE FLUID LEVEL WARNING LIGHT SYSTEM>WIRING DIAGRAM>WITH EYESIGHT .
- CHECK OPERATION OF ELECTRONIC PARKING BRAKE.
Operate the parking brake switch.
Does the electronic parking brake operate properly?
Yes: Ask the customer whether the following switch operation was performed.
- Operated slowly over one second or more.
- Repeated ON/OFF operation several times within one second.
When the case above is true, the system is normal.
When it is normal, a temporary poor contact or noise interference is a possible cause.
No: Go to 2.
- CHECK HARNESS (CHECK FOR OPEN CIRCUIT).
- Turn the ignition switch to OFF.
- Disconnect the connectors from the VDC Control Module & H/U and parking brake switch.
- Measure the resistance between VDC Control Module & H/U and parking brake switch connector.
Connector & terminal
(B310) No. 17 - (AD3) No. 2:
(B310) No. 18 - (AD3) No. 1:
(B310) No. 19 - (AD3) No. 5:
(B310) No. 24 - (AD3) No. 6:
Is the resistance less than 1 Ω?
Yes: Go to 3.
No: Repair harness and connector between VDC Control Module & H/U and parking brake switch connector.
- CHECK HARNESS (CHECK FOR GROUND SHORT CIRCUIT).
Measure the resistance between the parking brake switch connector and chassis ground.
Connector & terminal
(AD3) No. 2 - Chassis ground:
(AD3) No. 1 - Chassis ground:
(AD3) No. 5 - Chassis ground:
(AD3) No. 6 - Chassis ground:
Is the resistance 1 MΩ or more?
Yes: Go to 4.
No: Repair ground short of harness between VDC Control Module & H/U and parking brake switch connector.
- CHECK HARNESS (CHECK FOR SHORT CIRCUIT TO POWER SUPPLY).
- Turn the ignition switch to ON.
- Measure the voltage between parking brake switch connector and chassis ground.
Connector & terminal
(AD3) No. 2 (+) - Chassis ground (-):
(AD3) No. 1 (+) - Chassis ground (-):
(AD3) No. 5 (+) - Chassis ground (-):
(AD3) No. 6 (+) - Chassis ground (-):
Is the voltage less than 1 V?
Yes: Go to 5.
No: Repair short to power supply of harness between VDC Control Module & H/U and parking brake switch connector.
- CHECK PARKING BRAKE SWITCH.
Check the parking brake switch. Refer to PARKING BRAKE>PARKING BRAKE SWITCH>INSPECTION .
Is the check result OK?
Yes: Go to 6.
No: Replace the parking brake switch. Refer to PARKING BRAKE>PARKING BRAKE SWITCH .
- CHECK VDC CONTROL MODULE & H/U.
- Connect all connectors.
- Perform the Clear Memory Mode. Refer to VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)>CLEAR MEMORY MODE .
- Perform the Inspection Mode. Refer to VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)>INSPECTION MODE .
- Read the DTC. Refer to VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)>READ DIAGNOSTIC TROUBLE CODE (DTC) .
Is the same DTC displayed?
Yes: Replace the VDC Control Module & H/U. Refer to VEHICLE DYNAMICS CONTROL (VDC)>VDC CONTROL MODULE AND HYDRAULIC CONTROL UNIT (VDCCM & H/U) .
No: Go to 7.
- CHECK DETECTION OF OTHER DTCS FOR VDC.
Refer to VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)>READ DIAGNOSTIC TROUBLE CODE (DTC) .
Is any other DTC displayed?
Yes: Perform the diagnosis according to DTC. Refer to VEHICLE DYNAMICS CONTROL (VDC) (DIAGNOSTICS)>LIST OF DIAGNOSTIC TROUBLE CODE (DTC) .
No: Currently, it is normal. There may have been a temporary poor contact in the harness and connector or a temporary noise interference.