ABS CAN Message Missing
(P0600) ABS CAN MESSAGE MISSING
When Monitored and Set Condition
- When Monitored: CAN Bus Circuit error not present, 1 second after ignition on and not in Park or Neutral, no System Overvoltage or System Undervoltage conditions present, or transmission in Park or Neutral and engine RPM greater than 850 RPM.
- Set Condition: This DTC is set when a CAN ID was not received in the required time are not being sent from the CAB.
NOTE: The CAB is powered by the run only ignition feed. This means that this DTC will be set if the key is placed in the start position with the transmission in gear or if in Park or Neutral and the engine RPM is greater than 850 RPM.
POSSIBLE CAUSES
- VEHICLE STARTED IN GEAR
- CAN BUS CIRCUIT DTC PRESENT
- ABS DTCS PRESENT
- CAN C BUS +/- CIRCUIT OPEN
- CONTROLLER ANTILOCK BRAKE MODULE
- TRANSMISSION CONTROL MODULE
Diagnostic Test
1. PRE-DIAGNOSTIC CHECK OUT
Note: Low fluid level can be the cause of many transmission problems. If the fluid level is low, locate and repair the leak then check and adjust the fluid level in accordance with the Service Information.
Note: Always perform diagnostics with a fully charged battery to avoid false symptoms.
With the DRB III*, read the engine DTCs. Check and repair all engine DTCs prior to performing transmission symptom diagnostics.
With the DRB III*, read and record all Transmission DTCs.
Note: Check connectors - Clean/repair as necessary. Poor pin to terminal connections can set DTCs.
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors. Repair as necessary.
Most DTCs set on start up but some must be set by driving the vehicle such that all diagnostic monitors have run.
Note: Verify flash level of transmission controller. Some problems are corrected by software upgrades to the transmission controller.
Note: Check for any Technical Service Bulletins that may apply.
Perform this procedure prior to Symptom diagnosis.
Continue
Go To 2
2. ABS DTC SET WHEN VEHICLE STARTED IN GEAR OTHER THAN PARK OR NEUTRAL
Note: This DTC can be erroneously set if the vehicle was started in gear or with the engine running.
Turn the ignition on.
With the DRB III*, erase this DTC.
Turn the ignition off, then back on.
Monitor the DRB III* for this DTC.
Did DTC (P0600) ABS CAN MESSAGE MISSING set again?
Yes>>Go To 3
Note: If the ignition switch is moved to the RUN/START position with the shift lever not in the Park or Neutral position or the RUN/START position with the engine RPM >850, a (P0600) ABS CAN MESSAGE MISSING DTC will set. Erase DTC and return to customer.
No>>Test Complete.
3. (P0720) CAN BUS CIRCUIT DTC PRESENT
With the DRB III*, read Transmission DTCs.
Note: If DTC (P0720) CAN BUS CIRCUIT is present, perform diagnostics on that symptom first.
Is DTC (P0720) CAN BUS CIRCUIT present?
Yes>>Refer to the Transmission - Electrical Diagnostics category and perform the appropriate symptom. Perform NAG1 TRANSMISSION VERIFICATION TEST.
No>>Go To 4
4. CHECK TO SEE IF ABS DTCS ARE PRESENT
Turn the ignition on.
With the DRB III*, read ABS DTCs.
Are any performance or bus related ABS DTCs present?
Yes>>Refer to the Brakes - ABS Electrical Diagnostics category and perform the appropriate symptom.
Perform NAG1 TRANSMISSION VERIFICATION TEST. Verification Tests
No>>Go To 5
5. CAN C BUS +/- CIRCUIT OPEN
Turn the ignition off.
Disconnect the CAB harness connector.
Disconnect the TCM C3 harness connector.
Note: Check connectors - Clean/repair as necessary.
Measure the resistance of the CAN C Bus (+) circuit from the CAB harness connector to the TCM C3 harness connector.
Measure the resistance of the CAN C Bus (-) circuit from the CAB harness connector to the TCM C3 harness connector.
Is the resistance above 5.0 ohms on either circuit?
Yes>>Repair the faulty CAN C Bus circuit for an open.
Perform NAG1 TRANSMISSION VERIFICATION TEST.
No>>Go To 6
6. CAB- BRAKE MESSAGE MISSING
With the ignition off.
Replace and program the Controller Antilock Brake Module.
Turn the ignition on.
With the DRB III*, erase Transmission DTCs.
Start the engine.
With the brakes firmly applied, shift the gear selector into drive.
With the DRB III*, read Transmission DTCs.
Did DTC (P0600) ABS CAN MESSAGE MISSING set again?
Yes>>Replace the Transmission Control Module.
Perform NAG1 TRANSMISSION VERIFICATION TEST.
No>>Test Complete.