Missing Speed Difference Message

MISSING SPEED DIFFERENCE MESSAGE





For a complete wiring diagram refer to diagrams.
^ When Monitored:
When the Transfer Case Control Module receives a request to shift while vehicle speed is greater than 0 mph.
^ Set Condition:
The Transfer Case Control Module receives no ABS bus message for 5 seconds.

Possible Causes

- COMMUNICATION DTCS PRESENT
- ABS DTCS PRESENT
- INTERMITTENT MISSING SPEED DIFFERENCE MESSAGE DTC
- TRANSFER CASE CONTROL MODULE

1. COMMUNICATION DTCS PRESENT
Ignition on, engine not running.
With the DRBIII read DTCs in all modules.

Are there any Communication DTCs present?
Yes >>Refer to the Communication category and perform the appropriate diagnostic procedure.
Perform TRANSFER CASE VERIFICATION TEST. Transfer Case Verification Test
No >>Go To 2

2. ABS DTCS PRESENT With the DRBIII read ABS DTCs.

Are there any DTCs present in the ABS module?
Yes >>Perform the appropriate diagnostic procedure.
Perform TRANSFER CASE VERIFICATION TEST. Transfer Case Verification Test
No >>Go To 3

3. MISSING SPEED DIFFERENCE MESSAGE DTC PRESENT
With the DRBIII read Transfer Case DTCs. Record all DTC information.
With the DRBIII erase Transfer Case DTCs.
Start the engine and allow it to idle for at least 10 seconds.
Move the Transfer Case Mode Selector Switch to each position.
With the DRBIII read Transfer Case DTCs.

Does the DRBIII display MISSING SPEED DIFFERENCE MESSAGE?
Yes >>Go To 4
No >>Go To 5

4. TRANSFER CASE CONTROL MODULE
Using the wiring diagram as a guide, inspect the wiring and connectors relative to this DTC. Inspect all power and ground circuits. Repair as necessary.
If there are no Communication DTCs present or other possible causes remaining, view repair.

Repair
Replace the Transfer Case Control Module.
Perform TRANSFER CASE VERIFICATION TEST. Transfer Case Verification Test

5. INTERMITTENT WIRING AND CONNECTORS
The conditions necessary to set this DTC are not present at this time.
Using the schematics as a guide, inspect the wiring and connectors specific to this circuit.
Wiggle test the wiring harness and connectors while checking for shorted and open circuits.
Using the DRBIII monitor the data related to this circuit while performing the wiggle test. Look for the data to change or for the DTC to reset.

Were there any problems found?
Yes >>Repair as necessary.
Perform TRANSFER CASE VERIFICATION TEST. Transfer Case Verification Test
No >>Test Complete.