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CIS E Motronic ECU - Update

Group: 25

Number: 92-01

Date: Jan. 31, 1992

Subject:
Fuel System Management Control Module, Status

Model(s):
Passat, GLI, GTI, (GTX Canada only) from 1990 m.y.
Supersedes Technical Bulletin Group, No. 91-02

Condition

Due to hardware and software changes in the fuel system management control module (CIS-E Motronic) over the last few months, the part numbers of the fuel system management control modules, have been changed.

These changes were made to improve the interface between the fuel system management control module (CIS-E Motronic ECU) and the transmission control module (Digimat Automatic Transmission ECU) and to improve the performance of the vehicle.

The changes address the following:

^ Poor cold start at high ambient temperatures

^ Low idle when in drive gear position (automatic transmission only)

^ Stalling or surging when A/C clutch is disengaged

^ Poor acceleration performance

Service

When one of the above listed driveability complaints is encountered, establish the EPROM level of the Transmission Control Module (Digimat ECU) and the part number of the Fuel System Management Control Module (Motronic ECU) installed in the vehicle prior to servicing.

Passat vehicles with automatic transmissions:





^ connect VAC; 1551 Tester to the vehicle (Check Repair Group D3-20-1 and D3-30-1)

^ Switch VAG 1551 printer on





^ Display should be as shown above, displayed alternately

^ Select 1





^ press 0 then 2





^ press 0





^ read display to determine EPROM level

^ refer to chart below to determine correct part numbers and EPROM level





^ repeat for Engine Electronics O1 to determine correct fuel system management control module (ECU)

^ vehicles with manual transmission can use the following fuel system management control modules (ECU's)

^ California 8A0 907 404 BA or EA

^ 49 States and 8A0 907 404 CC, CB or FA Canada

CAUTION
Part numbers are for reference only. Always check with your Parts Department for latest parts information.