300E 4MATIC (124.230) L6-3.0L (103.985) (1990)
Engine Control Module: All Technical Service Bulletins
Campaign - CIS-E Control Unit False Fault Code 16
April 1990
TO:
OUR MERCEDES-BENZ PASSENGER CAR DEALERS
CAMPAIGN NO. 90-0442 CIS-E CONTROL UNIT WITH MALFUNCTION CODE 16 CALIFORNIA VERSION VEHICLES
MODEL YEAR 1990 WITH ENGINE 103 MODEL 124, 126 AND 201
Enclosed is a sample copy of a letter which all affected vehicle owners will receive in the near future.
This campaign is being initiated because field inspection of certain 1990 models has revealed a potential for a false triggering of the CHECK ENGINE
light on the dash.
On vehicles within the below listed serial number range, it is possible for the malfunction code 16 (ESR) to be stored in the CIS-E control unit (CHECK
ENGINE light comes on) even if there is no fault in any of the emission system and/or components.
Figure 1
Effective Serial Number
Model
Chassis End Number
124
B 065159
B 140136
F 122382
F 128655
126
A 499132
A 519940
201
F 649246
F 695025
The control unit must be replaced on these vehicles.
Note:
Only model year 1990 vehicles With CIS-E control units up to Bosch Production oode 950 (arrow, Figure 1) are affected.
A)
Vehicles in which the CHECK ENGINE light does not come on
On these vehicles, the CIS-E control unit is to be replaced without going through the test steps mentioned in paragraph "B".
B)
Vehicles in which the CHECK ENGINE light comes on
On these vehicles, the malfunction codes must be read with the impulse counter prior to replacing the control unit. If malfunction
code 16 is stored in memory, the test steps 21.0 to 22.2 in the model year 1990 introduction manual must be carried out, to assure
that there are no malfunctions in the emission system components.
Parts Information
Model
Part Name
Part Number
124.026
CIS-E control unit
201.029
"
011 545 05 32/05
124.030/090
CIS-E control unit