1996 PCED OBDI | SECTION 18: Diesel Diagnosis — 7.3L DI Engine |
AN1 KOEO AND KOER DIAGNOSTIC TROUBLE CODE (DTC) 0712
- DTC 0712 indicates that self test has detected a TFT sensor circuit input below the minimum acceptable voltage.
- Possible causes:
- Fluid level not to specification
- Damaged TFT sensor
- Short to GND or SIG RTN in TFT SIG harness circuit
- Damaged PCM
- Key on.
- Disconnect transmission 12-way (gray) connector. Inspect for damaged or pushed-out pins, corrosion, loose wires, etc. Service as necessary.
- Access TFT PID on NGS Tester.
Is voltage reading above 4.6v?
Yes | No |
Faulty TFT sensor. REFER to Section 07-01A of the Powertrain, Drivetrain Service Manual for TFT sensor replacement. | GO to AN2. |
AN2 CHECK TFT SIG CIRCUIT FOR SHORTS TO GROUND AND SIG RTN
- Key off.
- Transmission connector disconnected.
- Disconnect PCM. Inspect for damaged or pushed-out pins, corrosion, loose wires, etc. Service as necessary.
- Install breakout box, leave PCM disconnected.
- Measure resistance between Test Pin 37
- (TFT SIG) and Pins 25/51/76/77/103.
Is each resistance greater than 10,000 ohms?
Yes | No |
REPLACE damaged PCM. REMOVE breakout box. CLEAR DTCs and RETEST. | REPAIR short to ground in TFT Circuit 923 (O/BK). CLEAR DTCs and RETEST. |
AN3 KOEO AND KOER DTC 0713
- DTC 0713 indicates that self test has detected a TFT sensor circuit input above the maximum acceptable voltage.
- Possible causes:
- Fluid level not to specifications
- Damaged TFT sensor
- Short to VPWR in TFT SIG harness circuit
- Open in TFT SIG or SIG RTN harness circuit
- Damaged PCM
- Key off.
- Disconnect transmission 12-way (gray) connector. Inspect for damaged or pushed-out pins, corrosion, loose wires, etc. Service as necessary.
- Access TFT PID on NGS Tester.
Is voltage reading 5v?
Yes | No |
REPAIR short to power in Circuit 923 (O/BK). CLEAR DTCs and RETEST. | GO to AN4. |
AN4 SIGNAL RETURN CIRCUIT CHECK
- Key off.
- Check signal RTN Pin 8 to ground.
Is resistance less than 5 ohms?
Yes | No |
GO to AN5. | REPAIR open in signal return Circuit 359 (GR/Y). |
AN5 INDUCE OPPOSITE FAILURE
- Jumper TFT Pin 7 to signal return Pin 8.
Does voltage reading go to 0v?
Yes | No |
Faulty TFT sensor. REFER to Section 07-01A of the Powertrain, Drivetrain Service Manual for TFT sensor replacement. | GO to AN6. |
AN6 CHECK CONTINUITY OF TFT SIG CIRCUIT
- Key off.
- Transmission connector disconnected.
- Disconnect PCM. Inspect for damaged or pushed out pins, corrosion, loose wires, etc. Service as necessary.
- Install breakout box, leave PCM disconnected.
- Measure resistance between TFT SIG circuit at the transmission vehicle harness connector Pin 7 and Test Pin 37 (TFT SIG) at the breakout box.
Is resistance less than 5.0 ohms?
Yes | No |
REPLACE PCM. CLEAR DTCs and RETEST. | SERVICE open in TFT SIG harness Circuit 923 (O/BK). REMOVE breakout box. RECONNECT all components. RERUN Quick Test. |
AN7 KOEO AND KOER DIAGNOSTIC TROUBLE CODE (DTC) 1711: INCREASE/DECREASE TRANSMISSION FLUID TEMPERATURE
- DTC 1711 indicates that self test has detected a TFT sensor circuit input that was out of range. The TFT sensor input shows a failure occurred at either the low or high end of the acceptable range.
- Possible causes:
- Fluid level not to specification
- Fluid not at operating temperature
- Damaged TFT sensor
- Damaged PCM
- Clear continuous DTCs
- Drive vehicle to bring the transmission fluid to normal operating temperature.
- Activate KOEO and KOER Self Tests.
Is DTC 1711 still present?
Yes | No |
GO to AN8. | Transmission fluid was not at operating temperature. RERUN Quick Test. SERVICE other DTCs as necessary. |
AN8 CIRCUIT VOLTAGE CHECK
- Access TFT PID on NGS Tester.
Is reading above .2v and below 4v?
Yes | No |
REPLACE PCM. CLEAR DTCs and RETEST. | If DTC 0712 is also present, GO to AN1.
If DTC 0713 is also present, GO to AN3.
If DTC 1711 only, GO to Section 07-01A of the Powertrain, Drivetrain Service Manual for TFT sensor replacement. CLEAR DTCs and RETEST. |
AN9 CONTINUOUS MEMORY DIAGNOSTIC TROUBLE CODE (DTC) 0712: VERIFY TFT SIG VOLTAGE
- DTC 0712 indicates that self test has detected a TFT sensor circuit input that was below the minimum acceptable voltage (sometime during normal vehicle operation).
- Possible causes:
- Fluid level not to specification
- Short to GND or SIG RTN in TFT SIG harness circuit
- Damaged TFT sensor
- Damaged PCM
- Key on, engine off.
- Access TFT PID with NGS Tester.
Is TFT PID voltage less than 0.5 volts?
Yes | No |
The TFT SIG voltage is less than the acceptable minimum, but is not intermittent. GO to AN1. | The fault that produced Continuous Memory DTC 0712 is intermittent. GO to AN10. |
AN10 TRANSMISSION HARNESS CHECK
- Key on, engine off.
- Access TFT PID with NGS Tester.
- Observe TFT PID while performing the following:
- Shake, wiggle TFT SIG and SIG RTN circuits between transmission and PCM.
Does TFT valve fluctuate or go below .5v?
Yes | No |
REPAIR harness as required. CLEAR DTCs and RETEST. | Intermittent unable to duplicate. |
AN11 CONTINUOUS MEMORY DIAGNOSTIC TROUBLE CODE (DTC) 0713: VERIFY TFT SIG VOLTAGE
- Continuous Memory DTC 0713 indicates that self test has detected a TFT sensor circuit input that was above the maximum acceptable voltage (sometime during normal vehicle operation in the past).
- Possible causes:
- Fluid level not to specification
- Open in TFT SIG or SIG RTN harness circuit
- Short to VPWR in TFT SIG harness circuit
- Damaged TFT sensor
- Damaged PCM
- Key on, engine off.
- Access TFT PID with NGS Tester.
Is TFT PID voltage greater than 4.8 volts?
Yes | No |
The TFT SIG voltage is greater than the acceptable maximum, but is not intermittent. GO to AN3. | The fault that produced Continuous Memory DTC 0713 is intermittent. GO to AN12. |
AN12 TRANSMISSION HARNESS CHECK
- Key on, engine off.
- Access TFT PID with NGS Tester.
- Observe TFT PID while performing the following:
- Shake and wiggle TFT SIG and SIG RTN circuits between transmission and PCM.
Does TFT PID valve fluctuate or go above 4.6v?
Yes | No |
REPAIR harness as required. CLEAR DTCs and RETEST. | Intermittent unable to duplicate. |
AN13 CONTINUOUS MEMORY DIAGNOSTIC TROUBLE CODE (DTC) 1783: RERUN KOEO SELF TEST
- Continuous Memory DTC 1783 indicates a transmission over temperature condition occurred.
- Possible causes:
- Damaged transmission cooling system
- Excessive loading, e.g., trailer towing
- Damaged clutch
- Improper transmission fluid level
- Damaged transmission connector
- Key off.
- Disconnect transmission connector. Inspect for damaged or pushed-out pins, corrosion, loose wires, etc. Service as necessary and reconnect.
Note: If DTC 1783 repeats and no other DTC is generated, refer to Section 07-01A of the Powertrain, Drivetrain Service Manual for transmission over temperature condition.
- Rerun KOEO Self Test and record all DTCs.
Any transmission related DTCs generated?
Yes | No |
ADDRESS any transmission-related DTCs by referring to Diagnostic Trouble Code Description charts in Scan Tool Diagnostic Test Procedures section. | REFER to Section 07-01A of the Powertrain, Drivetrain Service Manual for over temperature condition (check clutch, transmission fluid level etc.). |