U1163

DTC U1163

CIRCUIT DESCRIPTION
The power door serial data line provides a means for information exchange among the vehicle door modules. Door module information on inputs and commanded outputs are converted to power door serial data for exchange among the door modules. The DDM periodically addresses each module on the power door serial data line. When a module does not respond to the DDM, the DTC for that module is set.

The Driver Door Module (DDM) can also take information from other modules connected to the class 2 serial data circuit and relay the command to the power door serial data circuit. Vehicle power mode messages (ignition switch position) from the DIM is an example.

CONDITIONS FOR RUNNING THE DTC
- Diagnostic trouble codes B1982 and B1983 do not have a current status.
- The driver door module has power.
- The driver door module has received an input or a class 2 wake-up message.

CONDITIONS FOR SETTING THE DTC
When a response message from the passenger door module, or, a rear door module, or, the driver door switch assembly (DDSA) is not received by the DDM within 2 seconds of the DDM's request, the DTC is set.

CONDITIONS FOR CLEARING THE DTC
- A current DTC will clear when a response message from the failed door module or driver door switch assembly is detected or at the end of the current ignition cycle.
- A history DTC will clear upon receipt of a scan tool Clear DTCs command.

TEST DESCRIPTION

Steps 1-2:

Steps 3-5:

Steps 6-8:

Steps 9-13:

Steps 14-22:

The number(s) below refer to the step number(s) on the diagnostic table.
1. Diagnostic trouble codes U1161, U1162 and U1170 set simultaneously indicate a total malfunction of the power door serial data circuit.
2. When DTCs U1161 and U1162 set simultaneously but U1170 does not set, the malfunction may be caused by an open in the power door serial data circuit between the DDM and the rear fuse block, or, by an open in the ground circuit shared by the passenger front door module and the rear door module, between splice S207 and the body ground terminal (G201).
3. Loss of communications with individual modules may be due to an unpowered module. This step verifies that the module has a power supply.
4. Loss of communication with individual modules may be due to an ungrounded module. This step verifies that the module has a ground supply.
5. The power door serial data circuit is shorted to voltage or ground. The condition may be due to the wiring or due to a malfunction in one of the modules. When testing the wiring for a short, make sure there is not a module connected to the wire being tested.
7. Operating the window and locks from the scan tool via the class 2 serial data circuit isolates the cause of the malfunction to the power door serial data circuit.
8. The DDM has the capability of controlling the driver door functions. The malfunction must be due to the DDSA.
9. The following steps isolate the door module which is preventing power door serial data communications.
13. The open in the power door serial data circuit is between the DDM and the rear fuse block.