Description of On-Board Diagnostic System

Notes on the BMW DIAGNOSTIC SYSTEM:

Control Unit identification:

Control units up to model year '91 can be identified by the hardware version 1.1 or 1.2.

Control units as of model year '92 can be identified by the hardware version 2.x.

Various country-specific versions only effect the FH/SHD system. The differentiation between ECE or US version is made by way of an additional cable (GM Pin D13).

ZKE Part Systems:

"*" indicates whether a part system is recognized by the general module as "installed". If a defect code is stored for the system it is represented in inverse form (white background).

Defect Code Memory:

In software versions 4.2 and 4.3 (see identification page) the defect code memory is cleared when ZKE is selected (reasons: Incorrect storage during operation). The defect code memory is no longer cleared as of version 5.0.

The activated relay is stored as defective during simulation of the outputs. For this reason, the defect code memory is cleared automatically after simulation (in all versions). The defect codes are stored once again when the systems are operated from the vehicle.

Current defects are indicated by the text display current defect or blocking protection active. These defect codes cannot be cleared from the memory.

Troubleshooting:

Notes:

- Troubleshooting with the BMW DIAGNOSTIC SYSTEM
- Battery charged, U-min = 12 V
- When switched oft and in working order, a protection relay switches on again when ignition is switched off and on.
- The power supply to the general module is interrupted when the relay module is removed.

The following sections apply to the individual part Systems:

- Windscreen wiper control defective.
Testing and Inspection
- Power windows defective.
Testing and Inspection
- Sunroof defective.
[1][2]Component Tests and General Diagnostics
- Central locking system defective.
Testing and Inspection
- Door lock heating defective.
Testing and Inspection
- Headlight washer system defective.
Testing and Inspection
- Windscreen wiper pressure control defective.
Testing and Inspection
- Interior lights control defective.
Testing and Inspection

Important!

When the supply voltage is applied (terminal 30 at Pin A1), the ZKE general module detects which part systems are installed in the vehicle. Undefined contacting when plugging in the module can result in systems not being detected. Therefore:

Disconnect the vehicle battery before installing a ZKE general module!

or

Disconnect the vehicle battery for at least 5 seconds after installing a ZKE general module.