Operation CHARM: Car repair manuals for everyone.

Manual Temperature Control






U0010 - Can Interior Bus

For a complete wiring diagram, refer to.

When Monitored: Continuously

Set Condition: If the CAN Interior Bus (+) or CAN Interior Bus (-) circuit is open, short to voltage, or short to ground.






Test Step 1 - Verify the DTC is Active

Turn the ignition ON.

With the scan tool, read HVAC DTCs.

Does the scan tool display this DTC as active?

Yes

Go to Test Step 2 => [ Test Step 2 - Check for an Active CAN Bus Related DTCs in the Totally
Integrated Power Module ]

No

If the DTC is stored, check for an intermittent condition by inspecting the related wiring harness for chafed, pierced, pinched, and partially broken wires. Also, inspect the related connectors for broken, bent, pushed out, spread, corroded, or contaminated terminals.

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

Test Step 2 - Check for an Active CAN Bus Related DTCs in the Totally Integrated Power Module

With the scan tool, read the totally integrated power module DTCs

Does the scan tool display any active CAN Bus related DTCs?

Yes

Diagnose and repair the DTCs.

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

No

Go to Test Step 3 => [ Test Step 3 - Check CAN Interior Bus (+) Circuit for an Open ]

Test Step 3 - Check CAN Interior Bus (+) Circuit for an Open

Turn the ignition OFF.

Disconnect the negative battery cable.

Disconnect the A/C heater control (3 ZONE ATC) 32 way harness connector.

Disconnect the totally integrated power module C7 harness connector.

Measure the resistance of the CAN Interior Bus (+) circuit between the totally integrated power module C7 harness connector and the A/C heater control (3 ZONE ATC) 32 way harness connector.

Is the resistance less than 2.0 ohms?

Yes

Go to Test Step 4 => [ Test Step 4 - Check CAN Interior Bus (-) Circuit for an Open ]

No

Repair the CAN Interior Bus (+) circuit for an open.

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

Test Step 4 - Check CAN Interior Bus (-) Circuit for an Open

Measure the resistance of the CAN Interior Bus (-) circuit between the totally integrated power module C7 connector and the A/C heater control (3 ZONE ATC) 32 way harness connector.

Is the resistance less than 2.0 ohms?

Yes

Go to Test Step 5 => [ Test Step 5 - Check CAN C Interior Bus (+) Circuit for a Short to
Ground ]

No

Repair the CAN Interior Bus (-) circuit for an open.

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

Test Step 5 - Check CAN C Interior Bus (+) Circuit for a Short to Ground

Measure the resistance between ground and the CAN C Interior Bus 125K (+) circuit in the A/C heater control (3 ZONE ATC) 32 way harness connector.

Is the resistance more than 1000.0 ohms?

Yes

Go to Test Step 6 => [ Test Step 6 - Check CAN C Interior Bus (-) Circuit for a Short to
Ground ]

No

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

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

Test Step 6 - Check CAN C Interior Bus (-) Circuit for a Short to Ground

Measure the resistance between ground and the CAN C Interior Bus 125K (-) circuit in the A/C heater control (3 ZONE ATC) 32 way harness connector.

Is the resistance more than 1000.0 ohms?

Yes

Go to Test Step 7 => [ Test Step 7 - Check CAN C Interior Bus (+) Circuit for a Short to
Voltage ]

No

Repair the CAN C Interior Bus (-) circuit for a short to ground.

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

Test Step 7 - Check CAN C Interior Bus (+) Circuit for a Short to Voltage

Turn the ignition ON.

Measure the voltage of the CAN C Interior Bus 125K (+) circuit in the A/C heater control (3 ZONE ATC) 32 way harness connector.

Is the voltage less than 0.2 volts?

Yes

Go to Test Step 8 => [ Test Step 8 - Check CAN C Interior Bus (-) Circuit for a Short to
Voltage ]

No

Repair the CAN C Interior Bus (+) circuit for a short to voltage.

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

Test Step 8 - Check CAN C Interior Bus (-) Circuit for a Short to Voltage

Measure the voltage of the CAN C Interior Bus 125K (-) circuit in the A/C heater control (3 ZONE ATC) 32 way harness connector.

Is the voltage less than 0.2 volts?

Yes

Replace the A/C heater control.

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

No

Repair the CAN C Interior Bus (-) circuit for a short to voltage.

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