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EEC IV Processor - MIL ON/Code 41 Set

Article No.
93-8-14

April 14, 1993

LAMP - "MALFUNCTION INDICATOR LAMP" - ON AND CODE 41 (HEGO INDICATING RICH/LEAN) IN CONTINUOUS MEMORY - 7.5L WITH E40D TRANSMISSION



LIGHT TRUCK:
1989-93 E-250, E-350, F-250, F-350



CALIBRATION:
9-98A-R00, 0-98A-R05, 0-98A-R10, 1-98A-R00, 2-98A-R10, 0-98E-R10, 0-98E-R05, 1-98E-R00, 2-98E-R00, 2-98E-R10

WARNING:
THIS MODIFICATION IS AUTHORIZED ONLY FOR THE LISTED ENGINE. PERFORMING THIS MODIFICATION ON OTHER ENGINE CALIBRATIONS IS UNAUTHORIZED AND COULD CREATE LIABILITY UNDER APPLICABLE FEDERAL OR LOCAL LAWS.

ISSUE:
Vehicles equipped with 7.5L engines and E40D transmissions may exhibit a Check Engine Light "MIL", On and code 41 in continuous memory. The strategy is performing the HEGO Test during open-loop engine operation. This in combination with a green vehicle KAM (Keep Alive Memory) results in no HEGO switching during VIP (Vehicle In Progress) test conditions and activates the MIL light.

ACTION:
Diagnose for proper operation of the "MIL" Light. Refer to the following procedure for service details.


SERVICE PROCEDURE

1. Follow the appropriate Quick Test Procedure in the Powertrain Control/Emission Diagnostic Manual for "MIL" light.





2. If a code 41 appears in continuous memory and pass code 11 appears in the KOEO (Key On Engine Off) and KOER (Key On Engine RUNNING) Tests, then replace the EEC IV processor. Refer to the EEC IV Processor Reference Chart in this article for correct parts usage.



3. If a code 41 appears in continuous memory and fault codes appear in the KOEO or KOER tests, other concerns may be occurring. Service them as required.

NOTE:
DO NOT REPLACE THE PROCESSOR UNTIL BOTH KOEO AND KOER SHOW PASS CODES.





Obtain an Authorized Modifications Decal and list the date, dealer number, and summary of alterations performed. Select a prominent place adjacent to the Vehicle Emission Control Information Decal suitable for installing the Authorized Modifications Decal. Clean the area, install the decal, and cover it with a clear plastic decal shield.



PART NUMBER PART NAME CLASS

F2PZ-12A650-AXA EEC IV Processor B
F2PZ-12A650-AWA EEC IV Processor B



OTHER APPLICABLE ARTICLES: NONE

WARRANTY STATUS:
Eligible Under Bumper To Bumper warranty Coverage For 1992/93 Models and Emissions Warranty Coverage

OPERATION DESCRIPTION TIME
930814A Perform Quick Test, 0.9 Hr.
Replace PCM, Run Final
Quick Test - 1989-93
Econoline, 1989-1991
F-Series
930814B Perform Quick Test, 1.4 Hrs.
Replace PCM, Run Final
Quick Test - 1992-93
F-Series

DEALER CODING
BASIC PART NO. CONDITION CODE
12A650 08

OASIS CODES: 206000