No Communications With the Electronic Unit

Check





1 That the ignition is switched on and the electronic unit is supplied with battery voltage.

2 That battery voltage is present across pins 16 and 4 of the test socket (if the voltage is correct, the ISAT display will light up when the ISAT is plugged into the test socket).

3 The connection between the test socket and the electronic unit.

4 If the ISAT still cannot establish communication with the electronic unit:

Symptom 1

- The seat can be operated by the manual controls but when the manual control is released the seat returns to its original position.

Probable Cause Of Fault 1

- Fault in the memory button assembly. The memory buttons are constantly activated.

Diagnostic Procedure 1

Checking the Operation of Pushbuttons and Manual Controls

Symptom 2

- The electronic unit is completely dead and does not react in any way to commands from either the memory pushbuttons or the manual controls.

Probable Cause Of Fault 2

- The electronic unit has detected an internal fault of such a nature that all functions have been blocked.

Diagnostic Procedure 2

Checking the Basics