EEC IV - Quick Test Fault Codes

83ford7 Article No. 83-21-17

EEC IV - "QUICK TEST" - (4.9L) - FAULT CODES


LIGHT TRUCKS 1984 E, F AND BRONCO

1984 Light Trucks with the 4.9L EEC IV may produce "quick test" fault codes when the EEC system is actually operating correctly. The procedure listed below should be used as a guide to determine if one of the subject engines has an EEC IV concern.

Fault Code 23
^ Inspect throttle linkage to assure that carburetor has returned to proper closed throttle position. Service as required and rerun Quick Test.
^ If Code 73 is present during the engine running test, along with Code 23, service using the proper diagnostic procedures.
^ If code 73 is not present, no servicing is required at this time.

Fault Code 41: Calibration 4-51 D Only

^ Inspect the vacuum lines and electrical harness for proper installation and for damage. Service as required.
^ Run the vehicle at 2000 RPM for 2 minutes to warm up the engine. Repeat Quick Test to verify Code 41.
^ If Code 41 is still present, rerun Quick Test while manually holding the engine at 2400 to 2600 RPM. If Code 41 is still present, service, using proper diagnostic procedures. If Code 41 is not present, but other 40 series codes are present, service these codes using proper diagnositic procedures. Disregard any Non-40 series codes generated during this testing because they are a direct result of manually holding the engine at the higher RPM.

NOTE: Any retesting to assure proper service of the above 40 series codes must be performed at the higher RPM.

Green (new) engine characterstics may cause fault code 42 to occur on some 1984 4.9L vehicles. When this code is encountered, the following actions should be taken.
Fault Code 42: All Calibrations Except 4-51 D

^ Code 42 may occur due to green engine (less than 1,000 miles) characteristics. To assure system integrity, perform normal diagnostic procedures and inspect the fuel system. If EEC system and fuel system check OK, no service is required at this time.

OTHER APPLICABLE ARTICLES: None
WARRANTY STATUS: "INFORMATION ONLY"