KOEO & KOER Codes (Hard Faults)
These codes indicate faults are present at time of testing. A hard fault may cause Malfunction Indicator Light (MIL) to go on and remain on until fault is repaired. If KOEO or KOER codes are retrieved during KOEO SELF-TEST or KOER SELF-TEST, use DIAGNOSTIC TROUBLE CODE REFERENCE CHARTS to find correct testing and repair procedures to be performed.
Continuous Memory Codes (Soft Faults)
These codes indicate a fault that may or may not be present at time of testing. These codes are used to diagnose intermittent problems. Continuous Memory Codes are retrieved after KOEO SELF-TEST. Some codes may turn on Malfunction Indicator Light (MIL). Corresponding soft fault trouble code will be retained in PCM memory. If fault does not reoccur within 40 warm-up cycles (80 cycles on some models), PCM will automatically clear code, or technician may clear codes from memory. See CLEARING CODES . Intermittent faults may be caused by a sensor, connector or wiring-related problem. See INTERMITTENTS in TESTS W/O CODES - 5.8L article.
| CAUTION | Continuous Memory Codes should be recorded when retrieved. These codes may be used to identify intermittent problems that exist after all KOEO and KOER codes have been repaired and a Code 111 (pass code) has been obtained. Some Continuous Memory Code faults may not be valid after KOEO and KOER codes are serviced. |
RETRIEVING CODES
Diagnostic trouble codes are retrieved from EEC-IV system through Data Link Connector (DLC). Various methods and test equipment may be used to access these codes
- Analog Volt-Ohmmeter (VOM).
- Scan tester.
- Malfunction Indicator Light (MIL) light.
- STAR series Tester.
| Application | Location |
|---|---|
| "F" Series | Below Right Side Of Instrument Panel |
DATA LINK CONNECTOR (DLC) LOCATIONS
Separator Code
Single 1/2-second separator pulse is issued 6-9 seconds after last KOEO code. Continuous Memory Codes (intermittent faults) are then displayed 6-9 seconds after 1/2-second separator code. (Scheme 337) Some digital test equipment may display separator code as "10" instead of "1".
Pass Codes
A Code 111 indicates no diagnostic trouble codes were recorded in that portion of test; system passes that portion of test. If Code 111 is not retrieved in KOEO SELF-TEST , codes retrieved during KOER SELF-TEST may not be valid. Code 111 (pass code) must be obtained in KOEO SELF-TEST. A Code 111-1-111 output during KOEO SELF-TEST indicates no KOEO code or Continuous Memory Code was recorded.
Continuous Memory Codes
Continuous Memory Codes are displayed after separator pulse code in KOEO SELF-TEST . These codes result from information stored by PCM during continuous self-test monitoring. These codes indicate faults recorded within last 40 engine starts (80 engine starts on some models). Fault may or may not be currently present. See DIAGNOSTIC TROUBLE CODE REFERENCE CHARTS . Use these codes for diagnosis only when KOEO SELF-TEST and KOER SELF-TEST result in Code 111.
Fast Codes
At start of KOEO SELF-TEST and after Wide Open Throttle (WOT) request in KOER SELF-TEST , PCM outputs short bursts of information, known as FAST CODES, which were used by manufacturer during assembly. These codes contain the identical information as slow codes, but are transmitted at 100 times the normal rate. With most equipment (except Super Star II tester), these code bursts are not visible. An entire code sequence lasts less than 1/2second.
Scheme 336
Scheme 337
CLEARING CODES
To clear codes from PCM memory, start KOEO SELF-TEST . When diagnostic trouble codes appear on test equipment or Malfunction Indicator Light (MIL), disconnect jumper wire from Self-Test Input (STI) connector. If using STAR series tester, unlatch center button. This procedure erases Continuous Memory Codes from PCM memory. If problem has not been corrected or fault is still present, hard code will immediately be reset in PCM memory.
| CAUTION | DO NOT disconnect vehicle battery to clear codes. This will erase stored operating information from Keep-Alive Memory (KAM). |
| CAUTION | When battery is disconnected, vehicle computer and memory systems may lose memory data. Driveability problems may exist until computer systems have completed a relearn cycle. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION before disconnecting battery. |
VISUAL CHECK
Complete all steps in BASIC TESTING - 5.8L article before proceeding to self-diagnostic tests. Inspect air cleaner and inlet ducting. Check coolant for proper level and mixture. Check transmission level and quality. Ensure all vacuum hoses and EEC-IV wiring harnesses are properly connected.
VEHICLE PREPARATION & EQUIPMENT HOOKUP
Apply parking brake, and place shift lever in Park (A/T) or Neutral (M/T) position. Block drive wheels. Turn off all electrical accessories. Connect appropriate test equipment to vehicle as follows
Scheme 338
- 1) Turn ignition off. Set VOM at 0-15V DC range. Connect positive lead of VOM to positive battery terminal.
- 2) Connect negative VOM lead to Self-Test Output (STO) terminal of Data Link Connector (DLC). (Scheme 338) Go to «KOEO SELF-TEST»(ref-24040-S38438425972001010400000). Activate KOEO SELF-TEST by connecting jumper wire from Self-Test Input (STI) pigtail to signal return (SIG RTN) terminal at DLC with ignition on.
Scan Tester
Follow manufacturers instructions to hook up equipment. Record diagnostic trouble codes.
STAR Series Tester
Turn ignition off. Connect color-coded adapter cable leads to diagnostic tester. Connect 2 service connectors of adapter cable to vehicle Data Link Connector (DLC) and STI pigtail connector. If using Super STAR II tester, select EEC-IV and Fast modes. Go to KOEO SELF-TEST .
Malfunction Indicator Light (MIL)
Turn ignition on. Connect a jumper wire between Self-Test Input (STI) pigtail and signal return (SIG RTN) terminal of Data Link Connector (DLC). (Scheme 339) Go to KOEO SELF-TEST.
Scheme 339
ADDITIONAL SYSTEM FUNCTIONS
Additional diagnostic system features are available to help diagnose driveability problems and service EEC-IV systems.
MIL is intended to alert driver of certain malfunctions in EEC-IV system. Light may also be used to retrieve diagnostic trouble codes stored in PCM. When hooked up for KOEO SELF-TEST or KOER SELF-TEST, light will display all codes which turn on light during vehicle operation.
Light should come on when ignition is turned on and go out when engine is started. If light comes on and then goes off during vehicle operation, code causing light to come on will be stored in PCM memory as a Continuous Memory Code. If light comes on during vehicle operation, vehicle should be inspected as soon as possible. Immediately turning off engine is not necessary; vehicle can be driven with light on.
Failure Mode Effects Management (FMEM) Code 998
FMEM mode allows system operation when sensors fail or transmit signals that are out of normal operating range. During FMEM mode, PCM substitutes a mid-range signal for defective sensor while continuing to monitor sensor. If faulty sensor's signals return to normal operating range, PCM will use those signals. A Code 998 will be displayed when FMEM mode is in effect.
SUMMARY
If no diagnostic trouble code is present but driveability problem still exists, go to TESTS W/O CODES - 5.8L article for diagnosis by symptom or intermittent diagnostic procedures.
CIRCUIT TESTS
Note. A breakout box, connected to vehicle harness at PCM, is necessary to perform most circuit tests. References to Test Pin No. found in CIRCUIT TEST steps refer to test terminals on manufacturer breakout box overlay. Circuit diagrams at beginning of each test identify circuit and wire colors.
HOW TO USE CIRCUIT TESTS
- 1) Ensure all non-EEC-IV related faults found while performing steps in «BASIC TESTING - 5.8L»(ref-24039) article have been corrected. Follow each test step in order until fault is found. When more than one code is retrieved, start with first code displayed.
- 2) CIRCUIT TESTS ensure electrical circuits are okay before sensors or other components are replaced. Always test circuits for continuity between sensor and PCM. Test all circuits for short to power, open or short to ground. Voltage Reference (VREF) and Voltage Power (VPWR) circuits should be tested with ignition on unless otherwise specified in CIRCUIT TESTS.
- 3) DO NOT measure voltage or resistance at PCM. DO NOT connect any test light unless specified in testing procedure. All measurements are made by probing rear of connector. Turn ignition off and isolate both ends of a circuit and turn ignition off when checking continuity.
- 4) Disconnect solenoids and switches from harness before measuring continuity and resistance or applying voltage. After each repair, reconnect all component connections and repeat QUICK TEST.
- 5) An open circuit is defined as a resistance reading of greater than 5 ohms. This specification tolerance may be too high for some items in EEC-IV system. If resistance approaches 5 ohms, always clean suspect connector and coat it with protective dielectric silicone grease. A short to ground is defined as a resistance reading of less than 10,000 ohms, unless stated otherwise in CIRCUIT TEST. NOTE: In the following tests, circuit diagrams and illustrations are courtesy of Ford Motor Co. CIRCUIT TESTS are grouped as follows: AA-C - No Start & Voltage Tests DA-DS - Input Sensor Tests FD - Additional Input Component Tests H-J - Fuel Control Systems KC-TG - PCM Output Tests
Code 513
Code 513 indicates PCM internal voltage is not to specification. Possible causes for this fault are
- Low battery voltage.
- Faulty PCM.
Turn ignition off. Measure voltage between battery terminals. If voltage is more than 10.5 volts, replace PCM and repeat QUICK TEST . If voltage is 10.5 volts or less, service charging system as necessary. Repeat QUICK TEST .