Tire Pressure Module (TPM)
9020-CAN BUS OFF
For a complete wiring diagram, Refer to the Wiring Information Electrical Diagrams.
- When Monitored:
Ignition on.
- Set Condition:
The TPM Module loses communication over the CAN Bus circuit. The circuit is continuously monitored.
1. ACTIVE DTC
NOTE: Review the vehicle repair history. If the Electronic Ignition Switch/Central Gateway Module has been replaced, ensure that it has been programmed correctly.
1. Ignition on, engine not running.
2. With a scan tool, read DTCs.
Is the DTC active at this time?
Yes
- Go To 3
No
- Go To 2
2. INTERMITTENT CONDITION
NOTE: Check for any of the follow conditions:
- Poor wire to terminal connection
- Corroded terminals
- Backed out or loose terminals
- Broken wire internal to the insulation
- Dirty (partial) module ground
Were any of the above condition present?
Yes
- Repair as necessary.
- Perform the TPM VERIFICATION TEST. Tire Pressure Monitor (TPM) Verification Test.
No
- DTC is not active at this time. Test complete.
3. OTHER COMMUNICATION DTCS
1. Using the scan tool, check other CAN B modules.
Are communication DTCs present?
Yes
- Perform the appropriate Loss of Communication diagnostic procedure.Communications - Verbose Codes
No
- Go To 4
4. MEASURE VOLTAGE AT TPM MODULE
1. Turn the ignition on.
2. Gain access to the TPM Module harness connector, but do not disconnect.
3. Backprobe and measure the voltage on both the CAN B Bus (+) and the CAN B (-) circuits.
NOTE: With the BUS active, the voltmeter should read, CAN B Bus (-) 4.65 - 4.98 volts and CAN B Bus (+) 0.39 - 0.46 volts.
Does the voltmeter read the correct voltages?
Yes
- Replace the TPM Module.
- Perform the TPM VERIFICATION TEST. Tire Pressure Monitor (TPM) Verification Test.
No - CAN B Bus (-)
- Repair the open in the CAN B Bus (-).
- Perform TPM VERIFICATION TEST. Tire Pressure Monitor (TPM) Verification Test.
No - CAN B Bus (+)
- Repair the open in the CAN B Bus (+).
- Perform TPM VERIFICATION TEST. Tire Pressure Monitor (TPM) Verification Test.