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U0011: Diagnosis and Testing






U0011 - CAN Interior Bus OFF Performance

For a complete wiring diagram, refer to.

When Monitored: With the ignition ON.

Set Condition: A module detects the CAN interior bus circuits short to ground, shorted together or short to voltage.






Test Step 1 - Test for an Intermittent Condition

Turn the ignition ON.

With the scan tool, record and erase DTCs.

Cycle the ignition from ON to OFF 3 times.

Turn the ignition ON.

With the scan tool, read active DTCs.

Does the scan tool display this DTC as active?

Yes

Go to Test Step 2.

No

The conditions that caused this code to set are not present at this time. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors.

Test Step 2 - Any CAN Interior Bus 125K Module Internal Short

When performing this step, turn the ignition OFF wait one minute before disconnecting any module. When the module is disconnected turn the ignition ON.

This step is to determine if the fault is internal within a module.

If the DTC becomes stored when a particular module is disconnected, that module is causing the DTC to set.

While monitoring the scan tool, disconnect each CAN interior bus 125K module except the TIPM itself, one at a time.

Test for this DTC to become active after disconnecting each CAN interior bus 125K module the vehicle is equipped with.

With all the CAN interior bus modules disconnected does the scan tool display this DTC as active?

Yes

Go to Test Step 3.

No

Replace the module that when disconnected caused this DTC to become stored.

Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior

Test Step 3 - CAN Interior Bus 125K (+) Circuit Short to Ground






Turn the ignition OFF.

Disconnect the TIPM harness connector.

Measure the resistance between ground and the CAN interior bus 125K (+) circuit at the TIPM harness connector.

Is the resistance less than 10k ohms?

Yes

Repair the CAN Interior Bus 125K (+) circuit for a short to ground.

Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior

No

Go to Test Step 4.

Test Step 4 - CAN Interior Bus 125K (-) Circuit Short to Ground






Measure the resistance between ground and the CAN interior bus 125K (-) circuit at the TIPM C7 harness connector.

Is the resistance less than 10k ohms?

Yes

Repair the circuit for a short to ground.

Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior

No

Go to Test Step 5.

Test Step 5 - CAN Interior Bus 125K (+) Circuit Short to the CAN Interior Bus 125K (-) Circuit






Measure the resistance between the CAN interior bus 125K (+) circuit and the CAN interior bus 125K (-) circuit at the TIPM harness connector.

Is the resistance less than 10k ohms?

Yes

Repair the (+) circuit for a short to the (-) circuit.

Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior

No

Go to Test Step 6.

Test Step 6 - CAN Interior Bus 125K (-) Circuit Short to Voltage






Turn the ignition ON.

Measure the voltage between ground and the CAN interior bus 125K (-) circuit at the TIPM harness connector.

Is the voltage more than 0.02 volts?

Yes

Repair the circuit for a short to voltage.

Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior

No

Go to Test Step 7.

Test Step 7 - CAN Interior Bus 125K (+) Circuit Short to Voltage






Measure the voltage between ground and the CAN interior bus 125K (+) circuit at the TIPM harness connector.

Is the voltage more than 0.02 volts?

Yes

Repair the circuit for a short to voltage.

Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior

No

Inspect the wiring and all module connectors for damage or shorted pins. If OK, replace and program the TIPM.

Perform the Body Verification Test. Refer to => Non-DTC Based Diagnostics. Body Interior