ECM - Production Change
86mercedes01TO: OUR MERCEDES-BENZ PASSENGER CAR DEALERS
DATE: January 1986 REF.NO. MBNA 07.3/3
SUBJECT: ON-BOARD DIAGNOSTIC READOUT VIA LAMBDA CONTROL TESTER M.Y.1986 M116/117 ENGINES
During production start-up, approximately 1,000 vehicles were equipped with a CIS-E control unit without the integrated microprocessor with failure indication via the Lambda control circuit. These control units are fully adequate for vehicle operation.
These vehicles can be diagnosed and tested by performing all of the CIS-E control unit tests, beginning on page 122 of the M.Y. 1986 Preliminary Introduction Manual. However, the test sections for Deceleration Shutoff (E) and for Idle and Full Load Contacts (F) cannot be performed on the above mentioned vehicles.
In place of the test section for Deceleration Shutoff (E) on page 139 of the M.Y. 1986 Introduction Manual, use the test section for Deceleration Shutoff (B), for the 102 engine, however, the current should be at least 60 mA instead of 45 mA. Refer to Service Microfiche Job No. 073-121 or page 80 of the M.Y. 1984 Introduction Manual for additional information.
The test for Idle and Full Load Contacts is to be performed as previously.
To determine if the control unit is equipped with a microprocessor with failure indication, connect the Lambda control tester and turn the ignition key to position 1.
On-Off Ratio Control Unit
100% without microprocessor
70% with microprocessor
NOTE: As of August 1985 (Bosch production code 548, located on the control unit), the Lambda control is integrated in the CIS-E control unit.