1996 PCED OBDI | SECTION 18: Diesel Diagnosis — 7.3L DI Engine |
AL1 ENTER KOEO OUTPUT STATE SELF TEST: CHECK TRANSMISSION ELECTRICAL OPERATION
- DTC 0741 indicates TCC electrical malfunction.
- DTC 1754 indicates CCS electrical malfunction.
- DTC 0750 indicates SS1 electrical malfunction.
- DTC 0755 indicates SS2 electrical malfunction.
- DTC 1746 indicates EPC electrical malfunction.
- DTC 1747 indicates EPC electrical malfunction.
- DTC 1748 indicates EPC electrical malfunction.
- Possible causes:
- Solenoid assembly damaged
- PCM damaged
- VPWR circuit open or shorted to GND
- Solenoid circuit open or, shorted to VPWR or GND
- Key off.
- Disconnect PCM. Check PCM connectors for corroded or damaged terminals and wires.
- Install breakout box. Connect PCM.
- Key on, engine off.
- Using NGS Tester, enter KOEO Output State Self Test.
- Observe transmission solenoid voltage reading on the DVOM and record. (Refer to schematic at beginning of this pinpoint test for circuit and pin numbers.)
Does the transmission solenoid circuit cycle 0.5 volts or greater on the DVOM?
| Yes | No |
|---|
| REFER to Section 07-01A of the Powertrain, Drivetrain Service Manual for solenoid diagnosis. | GO to AL2. |
AL2 ENTER KOEO OUTPUT STATE SELF TEST: CHECK TRANSMISSION ELECTRICAL OPERATION
Is the transmission solenoid circuit at 9v ± .5v?
| Yes | No |
|---|
| REFER to Section 07-01A of the Powertrain, Drivetrain Service Manual for solenoid diagnosis. | GO to AL3. |
AL3 CHECK CONTINUITY ON VPWR TO SOLENOIDS
- Key off.
- Disconnect transmission connector.
- Disconnect PCM relay.
- Measure resistance on Circuit 361 (R) from PCM relay to 12-way TR sensor connector Pins 1 and 12.
Is the resistance less than 5 ohms?
| Yes | No |
|---|
| GO to AL4. | SERVICE open in VPWR Circuit 361 (R). RECONNECT all components. COMPLETE PCM. RESET to CLEAR DTC. RERUN Quick Test. |
AL4 CHECK CONTINUITY OF SOLENOID SIGNAL AND VPWR HARNESS CIRCUIT
- Key off.
- 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 the suspect solenoid signal pin at the vehicle harness connector and the same suspect solenoid signal pin at the breakout box.
Is each resistance less than 5.0 ohms?
| Yes | No |
|---|
| GO to AL5. | SERVICE open circuit. REMOVE breakout box. RECONNECT all components. RERUN Quick Test. |
AL5 CHECK SOLENOID CIRCUIT FOR SHORT TO POWER OR GROUND
- Key off.
- Breakout box installed, PCM disconnected.
- Transmission connector disconnected.
- Refer to schematic and table at beginning of this pinpoint test.
- Measure resistance between the suspect solenoid signal pin and Test Pins 71/97 at the breakout box.
- Measure resistance between the suspect solenoid signal pin and Test Pins 51/76, 25, 77, 103 and 91 at the breakout box and chassis ground.
Is each resistance greater than 10,000 ohms?
| Yes | No |
|---|
| GO to AL6. | SERVICE short circuits. REMOVE breakout box. RECONNECT all components. RERUN Quick Test. |
AL6 CHECK APPROPRIATE SOLENOID
- Breakout box installed, PCM disconnected.
- Transmission connector connected.
- Key on, engine off.
- Measure voltage at the breakout box on the suspect test pin.
Is B+ present?
| Yes | No |
|---|
| REPLACE PCM. REMOVE breakout box. RECONNECT all components. CLEAR DTCs. RERUN Scan Tool Diagnostic Test. | SERVICE solenoid. REFER to Section 07-01A of the Powertrain, Drivetrain Service Manual for solenoid diagnosis. |
AL: Introduction