EEC IV Quick Test - False Service Codes

89ford06

Article No. 89-9-8

EEC IV QUICK TEST - FALSE SERVICE CODES - 1.9L EFI HO

FORD: 1987-89 ESCORT, EXP

LINCOLN-MERCURY: 1987 LYNX


ISSUE: EEC IV service codes 41, 42, 43, 65, 85 and 86 may be displayed in error during the EEC IV continuous memory quick test. These service codes could be false service codes generated by the sensitivity of the fuel control calibration. They may not be related to a certain component failure or drive symptom.

ACTION: If any of these service codes are present in continuous memory, use the following diagnostic procedure.

CODES WITH DRIVE SYMPTOMS:

1. When other service codes are present in addition to 41, 42, 43, 65, 85, and 86, CORRECT THOSE CODES FIRST. Follow the Quick Test Step diagnostic procedure in the Engine/Emission Diagnosis Shop Manual, Volume H and service as required.

2. If any or all of the service codes 41, 42, 43, 65, 85 and 86 and some or all of their drive symptoms are also present, resolve those codes. Follow the Quick Test Step diagnostic procedure in the Engine/Emission Diagnosis Shop Manual, Volume H and service as required.

3. If no problem is found after performing the Pinpoint Test, return to Section 2 of Volume H to check for other possible causes. DO NOT REPLACE ANY COMPONENTS UNLESS A SPECIFIC PINPOINT TEST FOR THE PART(S) FAILS.

4. After all service codes have been checked and any drive symptoms corrected, disconnect the negative (-) battery terminal for five minutes. This will clear Keep Alive Memory (KAM).

5. Reconnect the negative (-) battery terminal.

NOTE: INFORM THE CUSTOMER THAT THE CAR HAS RELEARNED "BASE IDLE" AND WILL NEED TO BE DRIVEN FIVE TO TEN MILES TO RELEARN ALL IDLE QUALITIES.

6. Idle the engine for two minutes to relearn base idle.

CODES WITH NO DRIVE SYMPTOMS:

1. If some or all service codes 41, 42, 43, 65, 85 and 86 are present without any drive symptoms, the codes are false.

2. Ignore the false service codes. No corrective action is required.

OTHER APPLICABLE ARTICLES: None
WARRANTY STATUS: INFORMATION ONLY
OASIS CODES: 680000