DTC P1A00[16] Differential Lock Coil Error (Power Supply) (Differential Lock)

Note

  • A deteriorated battery may cause this DTC to be set.

1. Differential lock control system check

Refer to "53.Driveline Control 3A.Troubleshooting(Differential Lock) diagnostic system check - differential lock controls".

2. Current DTC check

1) Connect the scan tool.

2) Turn OFF the ignition switch for 30 seconds or more.

3) Start the engine.

4) Observe the DTC information with a scan tool. Is a DTC set?

Yes

=>Go to Charging system inspection.

No

Go to Intermittent conditions of rear differential lock control system.

Refer to "204.Driveline, Axle 17D.Symptom intermittent conditions of differential lock control system".

3. Charging system inspection

1) Inspect the charging system. Is the result normal?

Refer to "1.Engine 1J.Electrical(4JJ3 with DPD) generator inspection".

Refer to "202.Engine 15C.Functional Inspection(4JJ3 with DPD) charging system check".

Refer to "1.Engine 1J.Electrical(4JJ3 without DPD) generator inspection".

Refer to "202.Engine 15C.Functional Inspection(4JJ3 without DPD) charging system check".

Refer to "1.Engine 1J.Electrical(RZ4E-TC) generator inspection".

Refer to "202.Engine 15C.Functional Inspection(RZ4E-TC) charging system check".

Yes

=>Go to Differential lock coil power supply circuit inspection.

No

Repair the charging system.

=>Go to Repair verification.

4. Differential lock coil power supply circuit inspection

1) Turn OFF the ignition switch.

2) Disconnect the rear differential lock control unit harness connector (C57).

3) Inspect the wire harnesses and connectors for the following. Is the result normal?

Wire harness to be inspected

  • Between the DIFF LOCK 10A fuse and the rear differential lock control unit (pin 16 of C57).

Refer to "LHD Differential Lock" in the ETM (wiring diagram). (Open using the ETM viewer.).

Refer to "RHD Differential Lock" in the ETM (wiring diagram). (Open using the ETM viewer.).

Inspection items

  • Open circuit
  • High resistance
  • Short to ground or short to other circuits
  • Terminal connection status

Yes

=>Go to Inspection for high resistance in rear differential lock control unit ground circuit.

No

Repair the circuit as necessary.

=>Go to Repair verification.

5. Inspection for high resistance in rear differential lock control unit ground circuit

1) Disconnect the differential lock coil harness connector (R39).

2) Inspect the ground circuit between the rear differential lock control unit (pin 15 of C57) and the rear differential lock control unit ground for high resistance. Is the result normal?

Refer to "LHD Differential Lock" in the ETM (wiring diagram). (Open using the ETM viewer.).

Refer to "RHD Differential Lock" in the ETM (wiring diagram). (Open using the ETM viewer.).

Yes

=>Go to Rear differential lock control unit ground inspection.

No

Repair the circuit as necessary.

=>Go to Repair verification.

6. Rear differential lock control unit ground inspection

1) Inspect the rear differential lock control unit ground point for corrosion or improper installation. Is the result normal?

Yes

=>Go to Rear differential lock control unit harness connector inspection.

No

Repair the rear differential lock control unit ground point as necessary.

=>Go to Repair verification.

7. Rear differential lock control unit harness connector inspection

1) Inspect for poor connections at the rear differential lock control unit harness connector (pins 15 and 16 of C57). Is the connection status normal?

Refer to "LHD Differential Lock" in the ETM (wiring diagram). (Open using the ETM viewer.).

Refer to "RHD Differential Lock" in the ETM (wiring diagram). (Open using the ETM viewer.).

Yes

Go to Intermittent conditions of rear differential lock control system.

Refer to "204.Driveline, Axle 17D.Symptom intermittent conditions of differential lock control system".

No

Repair the connections as necessary.

=>Go to Repair verification.

8. Repair verification

1) Clear the DTC with a scan tool.

2) Turn OFF the ignition switch for 30 seconds or more.

3) Start the engine.

4) Apply an electric load by turning ON the headlights, air conditioner, etc.

5) Observe the Differential Lock Coil-Battery Voltage Monitor parameter on the scan tool. Is the Differential Lock Coil-Battery Voltage Monitor parameter less than or equal to the specified value?

Value: 9 V

Yes

=>Go to Charging system inspection.

No

Observe the DTC information with a scan tool.