Diagnostic Trouble Code 112 EGR System is Set

SECTION:
2

GROUP:
28

NO.:
917

DATE:
May 1995

RE: Diagnostic Trouble Code (DTC) 1-1-2 with Motronic 1.8 MFI

960 1995 with EGR and air pump

REFERENCE: TP 2305201, SECTION 2 (23,28), MULTIPORT FUEL INJECTION (MFI) AND ELECTRONIC IGNITION SYSTEM (EI) MOTRONIC 1.8; 960 1991-

Diagnostic Trouble Code (DTC) 1-1-2 with Motronic 1.8 MFI

Some early production 1995 960s have a software condition in the Motronic 1.8 ECM affecting DTC 2-4-1. If there is an EGR fault resulting in storage of DTC 2-4-lit is converted to DTC 1-1-2 the first time the ignition is switched off.

If a customer complains that the warning light indicating a malfunction in the engine management system comes on, the fault could be interpreted as a fault in the engine control module (ECM) DTC 1-1-2 when it is in fact an EGR system DTC 2-4-1. To make sure which type of fault is actually being set, carry out the actions described in the operation method described on page 2.

The software condition in the control modules does not require control module replacement. The proper repair method follows.

This relates to the following cars:




960 cars, model year 1995 with EGR and air pump in the illustrated chassis number ranges:




A new revision of the software has been produced for the control module. The illustrated table gives the applicable replacement part numbers:

Use the following method when DTC 1-1-2 is set to reset the control module:

READ ENTIRE METHOD BEFORE STARTING PROCEDURE

CHECK THE EGR SYSTEM

Check and repair any malfunctions on the EGR system.

Reset the control module. (Do not replace the control module)

If there are no faults on the EGR system Start car with cold engine.

Test drive car for approx. 30 minutes highway driving, or until the warning light indicating a malfunction in the engine management system comes on. Check MIL (malfunction indicator lamp).

DO NOT TURN OFF THE IGNITION, read off any DTCs set in the ECM.

If the DTC set is 2-4-1 there is a fault in the EGR system after all.

- Check and repair the EGR system

It the DTC set is 1-1-2 there is a fault in the Motronic 1.8 MFI engine control module.

- Replace the Motronic 1.8 control module according to the method described in the service manual:

Multiport Fuel Injection (MFI) and Electronic Ignition (EI)

System Motronic 1.8 960 1991-, page 360;

WARRANTY STATEMENT:




Claims may be submitted under the New Car Limited Warranty when a manufacturing defect is present using claim type: 01