Checking the Power Supply and Ground Terminals

Checking The Power Supply And Ground Terminals

Power supply
The power supply to the Driver Door Module (DDM)/Passenger Door Module (PDM) is via two power inputs on the control module.
- Power input terminal # B7 (# 21) is supplied with voltage via a fuse to the battery (30 supply) and is common to both the driver door module (DDM) and passenger door module (PDM). The control module will not work if there is an open-circuit
- Power input terminal # B12 (# 26) is supplied with voltage via a fuse to the battery (30 supply) and is separate for the driver door module (DDM) and passenger door module (PDM). If there is an open-circuit, the control module will function, but it will not be possible to operate the window on that side.

Checking the power supply
Check the power supply cable from the battery to the driver door module (DDM)/passenger door module (PDM) terminal # B7 (B21). Check for an open-circuit. Check for loose connections. Check for contact resistance and oxidation. Check the fuse. The voltage should be approximately battery voltage.

Check the power supply cable from the battery to the driver door module (DDM)/passenger door module (PDM) terminal # B12 (B26). Check for an open-circuit. Check for loose connections. Check for contact resistance and oxidation. Check the fuse. The voltage should be approximately battery voltage.

Ground terminal







The Passenger Door Module (PDM)/Driver Door Module (DDM) has two power inputs. The ground inputs from the control module are connected via separate ground leads to a common ground terminal in the car body. See the relevant wiring diagram for further information about the ground terminal.
- Ground input terminal # B5 (# 19) is connected via a ground cable to the ground terminal in the car body. If there is an open-circuit, the control module will function, but it will not be possible to operate the window on that side
- Ground input terminal # B9 (# 23) is connected via a ground cable to the ground terminal in the car body. The control module will not work if there is an open-circuit.

Checking ground terminal
Check the ground lead between driver door module (DDM)/passenger door module (PDM) terminal # B5 (# 19) and the ground terminal in the car body. Check for an open-circuit. Check for loose connections. Check for contact resistance and oxidation. With the ignition on, the drop in voltage between the ground connection for the driver door module (DDM)/passenger door module (PDM) ground connection terminal # B5 (# 19) and the ground terminal must not be greater than 0.5 V.

Check the ground lead between driver door module (DDM)/passenger door module (PDM) terminal # B9 (# 23) and the ground terminal in the car body. Check for an open-circuit. Check for loose connections. Check for contact resistance and oxidation. With the ignition on, the drop in voltage between the ground connection for the driver door module (DDM)/passenger door module (PDM) ground connection terminal # B9 (# 23) and the ground terminal must not be greater than 0.5 V.

Remedy as necessary.

Other information:
- To connect the breakout box, see Connecting the breakout box. Connecting the Breakout Box
- For information about signals, see Signal Specification. Pinout Values and Diagnostic Parameters
- See the relevant wiring diagram for information about circuit and ground terminals in the bodywork.
- Checking wiring and terminals.