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C1402






C1402-TRANSFER CASE RANGE SELECT SWITCH CIRCUIT HIGH





For a complete wiring diagram, refer to the Wiring Information Electrical Diagrams.

- When Monitored:
With the ignition on.

- Set Condition:
Transfer Case Selector Switch voltage greater than 4.86 volts for five seconds.





1. TRANSFER CASE SELECTOR SWITCH VOLTAGE ABOVE 4.8 VOLTS
1. Ignition on, engine not running.
2. With the scan tool, read the Transfer Case Selector Switch voltage in the Instrument Cluster.

Is the voltage above 4.8 volts?

Yes

- Go To 2

No

- Go To 7

2. (K77) 5 VOLT SELECTOR SWITCH SUPPLY CIRCUIT SHORTED TO VOLTAGE




1. Turn the ignition off to the lock position.
2. Disconnect the Transfer Case Selector Switch harness connector.
3. Ignition on, engine not running.
4. Measure the voltage of the (K77) 5 Volt Selector Switch Supply circuit.

Is the voltage above 5.5 volts?

Yes

- Repair the (K77) 5 Volt Selector Switch Supply circuit for a short to voltage.
- Perform the TRANSFER CASE VERIFICATION TEST Transfer Case Verification Test

No

- Go To 3

3. (K977) MODE SELECT CIRCUIT SHORTED TO VOLTAGE




1. Measure the voltage of the (K977) Mode Select circuit.

Is there any voltage present?

Yes

- Repair the (K977) Mode Select circuit for a short to voltage.
- Perform the TRANSFER CASE VERIFICATION TEST Transfer Case Verification Test

No

- Go To 4

4. (K77) 5 VOLT SELECTOR SWITCH SUPPLY CIRCUIT OPEN




1. Turn the ignition off to the lock position.
2. Disconnect the Instrument Cluster C1 harness connector.
3. Measure the resistance of the (K77) 5 Volt Selector Switch Supply circuit between the Transfer Case Selector Switch harness connector and the Instrument Cluster C1 harness connector.

Is the resistance greater than 5.0 Ohms?

Yes

- Repair the open in the (K77) 5 Volt Selector Switch Supply circuit.
- Perform the TRANSFER CASE VERIFICATION TEST Transfer Case Verification Test

No

- Go To 5

5. (K977) MODE SELECT CIRCUIT OPEN




1. Turn the ignition off to the lock position.
2. Disconnect the Instrument Cluster C2 harness connector.
3. Measure the resistance of the (K977) Mode Select circuit between the Transfer Case Selector Switch harness connector and the Instrument Cluster C2 harness connector.

Is the resistance above 5.0 Ohms?

Yes

- Repair the open in the (K977) Mode Select circuit.
- Perform the TRANSFER CASE VERIFICATION TEST Transfer Case Verification Test

No

- Go To 6

6. TRANSFER CASE SELECTOR SWITCH INTERNALLY SHORTED TO VOLTAGE
1. Reconnect the Instrument Cluster C2 harness connector.
2. Ignition on, engine off.
3. With the scan tool, read the Transfer Case Selector Switch voltage in the Instrument Cluster.

Is DTC C1402 still present?

Yes

- Replace the Instrument Cluster.
- Perform the TRANSFER CASE VERIFICATION TEST Transfer Case Verification Test

No

- Replace the Transfer Case Selector Switch.
- Perform the TRANSFER CASE VERIFICATION TEST Transfer Case Verification Test

7. INTERMITTENT WIRING AND CONNECTORS
1. The conditions necessary to set this DTC are not present at this time.
2. Using the wiring diagram/schematic as a guide, inspect the wiring harness and connectors.
3. While monitoring the scan tool data relative to this circuit, wiggle test the wiring harness and connectors.
4. Look for the data to change or for the DTC to reset during the wiggle test.

Were any problems found?

Yes

- Repair as necessary.
- Perform the TRANSFER CASE VERIFICATION TEST Transfer Case Verification Test

No

- Test complete.