C1404

C1404- TRANSFER CASE RANGE POSITION SENSOR CIRCUIT LOW





When Monitored:
Ignition on. Battery voltage between 9 and 16 volts.

Set Condition:
FCM detects a short to ground on the Transfer Case Position Sensor signal circuit for 2 seconds.

Possible Causes
- INTERMITTENT CONDITION
- (T103) 5 VOLT SUPPLY CIRCUIT OPEN
- (T103) 5 VOLT SUPPLY CIRCUIT SHORTED TO GROUND
- (D201) MODE SENSOR A CIRCUIT SHORTED TO GROUND
- SHIFT MOTOR/MODE SENSOR ASSEMBLY
- FRONT CONTROL MODULE

Diagnostic Test
1. T-CASE POSITION SENSOR VOLTAGE BELOW 0.2 VOLTS





Ignition on, engine not running.
With the scan tool under Data Display, read the T-Case Position Sensor voltage.
Is the voltage below 0.2 volts?
Yes >>Go to 2
No >>Go to 8

2. (T103) 5 VOLT SUPPLY CIRCUIT VOLTAGE BELOW 0.2 VOLTS





Turn the ignition off.
Disconnect the Shift Motor/Mode Sensor connector.
Turn the ignition on.
Measure the voltage of the (T103) 5 Volt Supply circuit.
Is the voltage below 0.2 volts?
Yes >>Go to 3
No >>Go to 5

3. (T103) 5 VOLT SUPPLY CIRCUIT OPEN





Turn the ignition off.
Disconnect the Front Control Module C1 connector.
Measure the resistance of the (T103) 5 Volt Supply circuit.
Is the resistance above 5.0 ohms?
Yes >>Repair the (T103) 5 Volt Supply circuit for an open.
Perform the TRANSFER CASE VERIFICATION TEST VER 1. Transfer Case Verification Test
No >>Go to 4

4. (T103) 5 VOLT SUPPLY CIRCUIT SHORTED TO GROUND





Measure the resistance between ground and the (T103) 5 Volt Supply circuit.
Is the resistance below 5.0 ohms?
Yes >>Repair the (T103) 5 Volt Supply circuit for a short to ground.
Perform the TRANSFER CASE VERIFICATION TEST VER 1.
No >>Go to 7

5. SHIFT MOTOR/MODE SENSOR ASSEMBLY





With the scan tool under Data Display, read the T-Case Position Sensor voltage.
Is the voltage above 4.5 volts?
Yes >>Replace the Shift Motor/Mode Sensor Assembly.
Perform the TRANSFER CASE VERIFICATION TEST VER 1.
No >>Go to 6

6. (D201) MODE SENSOR A CIRCUIT SHORTED TO GROUND





Measure the resistance between ground and the (D201) Mode Sensor A circuit.
Is the resistance below 5.0 ohms?
Yes >>Repair the (D201) Mode Sensor A circuit for a short to ground.
Perform the TRANSFER CASE VERIFICATION TEST VER 1.
No >>Go to 7

7. FRONT CONTROL MODULE
View repair.
Repair
Replace the Front Control Module. Perform the TRANSFER CASE VERIFICATION TEST VER 1. Transfer Case Verification Test

8. INTERMITTENT WIRING AND CONNECTORS
The conditions necessary to set this DTC are not present at this time.
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.
While monitoring the scan tool data relative to this circuit, wiggle test the wiring and connectors.
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- VER 1.
No >>Test complete.