Passenger Compartment
U0208 - Lost Communication With Heated Seats Control Module
For a complete wiring diagram, refer to.
• When Monitored: With the ignition ON.
• Set Condition: The instrument cluster does not receive information from the heated seats control module.
Test Step 1 - Test For Intermittent Condition
• Turn the ignition ON.
• With the scan tool, record and erase DTCs.
• Wait 30 seconds.
• With the scan tool, read DTCs.
Does the scan tool display U0208 - Lost Communication With Heated Seats Control Module?
Yes
• Go to Test Step 2 => [ Test Step 2 - Check for Open TIPM Fuse M8 ]
No
• The condition that caused this code to set is not present at this time. 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 Open TIPM Fuse M8
• Inspect TIPM Fuse M8.
Is the fuse open?
Yes
• Go to Test Step 3 => [ Test Step 3 - Replace and Recheck TIPM Fuse M8 ]
No
• Go to Test Step 7 => [ Test Step 7 - Check Power to TIPM Fuse M8 ]
Test Step 3 - Replace and Recheck TIPM Fuse M8
• Turn the ignition OFF.
• Install a new TIPM Fuse M8.
• Turn the ignition ON.
• Operate the heated seat switch in both positions several times.
• Inspect TIPM Fuse M8.
Is the fuse open?
Yes
• Go to Test Step 4 => [ Test Step 4 - Check Fused Run Relay Output Circuit in TIPM for a
Short to Ground ]
No
• Using the wiring diagram/schematic as a guide, inspect the wiring and connectors for the cause of the open fuse and repair as necessary. If no problem found, perform the Body Verification Test. Refer to => Non - DTC Based Diagnostics. Body Interior
Test Step 4 - Check Fused Run Relay Output Circuit in TIPM for a Short to Ground
• Turn the ignition OFF.
• Remove TIPM fuse M8.
• Disconnect the TIPM C6 connector.
• Measure the resistance of the fused run relay output circuit between ground and the TIPM M8 fuse connector.
Is the resistance below 10k ohms?
Yes
• Replace the TIPM and fuse M8.
• Perform the Body Verification Test. Refer to => Non - DTC Based Diagnostics. Body Interior
No
• Go to Test Step 5 => [ Test Step 5 - Check Fused Run Relay Output Circuit for a Short to
Ground ]
Test Step 5 - Check Fused Run Relay Output Circuit for a Short to Ground
• Disconnect the heated seats module connector.
• Measure the resistance of the fused run relay output circuit between ground and the heated seats module connector.
Is the resistance below 10k ohms?
Yes
• Repair the fused run relay output circuit for a short to ground. Replace TIPM Fuse M8.
• Perform the Body Verification Test. Refer to => Non - DTC Based Diagnostics. Body Interior
No
• Go to Test Step 6 => [ Test Step 6 - Check Fused Run Relay Output Circuit for a Short to
the Ground Circuits ]
Test Step 6 - Check Fused Run Relay Output Circuit for a Short to the Ground Circuits
• Measure the resistance between the fused run relay output circuit and the ground circuit at the heated seats module connector.
Is the resistance below 10k ohms?
Yes
• Repair the fused run relay output circuit for a short to the ground circuit. Replace TIPM fuse M8.
• Perform the Body Verification Test. Refer to => Non - DTC Based Diagnostics. Body Interior
No
• Replace the heated seats module and TIPM fuse M8.
• Perform the Body Verification Test. Refer to => Non - DTC Based Diagnostics. Body Interior
Test Step 7 - Check Power to TIPM Fuse M8
• If not done previously, turn the ignition OFF, and then remove TIPM fuse M8.
• Turn the ignition ON.
• Using a 12 volt test light connected to ground, check the run relay output circuit at TIPM fuse M8 connector.
• The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery.
Does the test light illuminate brightly?
Yes
• Go to Test Step 8 => [ Test Step 8 - Check Power to Heated Seats Module ]
No
• Repair the run relay output circuit for an open.
• Perform the Body Verification Test. Refer to => Non - DTC Based Diagnostics. Body Interior
Test Step 8 - Check Power to Heated Seats Module
• Turn the ignition OFF.
• Reinstall TIPM fuse M8.
• Disconnect the heated seats module harness connector.
• Turn the ignition ON.
• Using a 12 volt test light connected to ground, check the fused run relay output circuit at the heated seat module connector.
• The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery.
Does the test light illuminate brightly?
Yes
• Go to Test Step 9 => [ Test Step 9 - Check LIN Bus Circuit Voltage to Heated Seats Module ]
No
• Go to Test Step 12 => [ Test Step 12 - Check Fused Run Relay Output Circuit for an Open ]
Test Step 9 - Check LIN Bus Circuit Voltage to Heated Seats Module
• Measure the voltage of the LIN bus circuit between the heated seats module connector and ground.
Is the voltage above 5.0 volts?
Yes
• Go to Test Step 10 => [ Test Step 10 - Check Ground Circuits for an Open ]
No
• Go to Test Step 11 => [ Test Step 11 - Check LIN Bus Circuit for an Open ]
Test Step 10 - Check Ground Circuits for an Open
• Using a 12 volt test light connected to 12 volts, check the ground circuit at the heated seats module connector.
• The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery.
Does the test light illuminate brightly?
Yes
• Replace the heated seats module.
• Perform the Body Verification Test. Refer to => Non - DTC Based Diagnostics. Body Interior
No
• Repair the ground circuit for an open.
• Perform the Body Verification Test. Refer to => Non - DTC Based Diagnostics. Body Interior
Test Step 11 - Check LIN Bus Circuit for an Open
• Turn the ignition OFF.
• Disconnect the instrument cluster C2 connector.
• Measure the resistance of the LIN bus circuit between the instrument cluster C2 connector and the heated seats module connector.
Is the resistance below 5.0 ohms?
Yes
• Replace the instrument cluster.
• Perform the Body Verification Test. Refer to => Non - DTC Based Diagnostics. Body Interior
No
• Repair the LIN bus circuit for an open.
• Perform the Body Verification Test. Refer to => Non - DTC Based Diagnostics. Body Interior
Test Step 12 - Check Fused Run Relay Output Circuit for an Open
• Turn the ignition OFF.
• Disconnect the TIPM C6 connector.
• Measure the resistance of the fused run relay output circuit between the TIPM C6 connector and the heated seats module connector.
Is the resistance below 5.0 ohms?
Yes
• Replace the TIPM..
• Perform the Body Verification Test. Refer to => Non - DTC Based Diagnostics. Body Interior
No
• Repair the fused run relay output circuit for an open.
• Perform the Body Verification Test. Refer to => Non - DTC Based Diagnostics. Body Interior