The torque converter clutch pulse width modulation (TCC PWM) solenoid valve is a normally closed solenoid used to control the apply and release of the converter clutch. The PCM operates the solenoid with a negative duty cycle. When vehicle operating conditions are appropriate to apply the TCC, the PCM immediately increases the duty cycle to approximately 42%. The PCM then ramps the duty cycle to approximately 90% to achieve full TCC apply pressure. When the solenoid is commanded OFF, the PCM senses low voltage. When the solenoid is commanded ON, the PCM senses high voltage.
When the PCM detects a continuous open, short to ground or short to power in the TCC PWM solenoid valve circuit, then DTC P1860 sets. DTC P1860 is a type A DTC .
• | The system voltage is 8-18 volts. |
• | The engine has been running for more than 5 seconds, and is not in fuel cut off. |
• | The TCC PWM solenoid valve duty cycle is less than 10% or greater than 90%. |
• | The PCM detects an open, short to ground or a short to power on the TCC PWM solenoid valve circuit within 5 seconds. |
• | The PCM illuminates the malfunction indicator lamp (MIL). |
• | The PCM inhibits TCC engagement. |
• | The PCM freezes shift adapts from being updated. |
• | The PCM stores DTC P1860 in PCM history. |
• | The PCM turns OFF the MIL during the third consecutive trip in which the diagnostic test runs and passes. |
• | A scan tool clears the DTC from PCM history. |
• | The PCM clears the DTC from PCM history if the vehicle completes 40 warm-up cycles without an emission-related diagnostic fault occurring. |
• | The PCM cancels the DTC default actions when the fault no longer exists and the ignition switch is OFF long enough in order to power down the PCM. |
• | Inspect the wiring at the PCM, the transmission 20-way connector and the TCC PWM solenoid valve 2-way connector for the following conditions: |
- | A backed out terminal |
- | A damaged terminal |
- | Reduced terminal tension |
- | A chafed wire |
- | A broken wire inside the insulation |
- | Moisture intrusion |
- | Corrosion |
• | Ensure that the transmission fluid is at the proper level. |
• | When diagnosing for an intermittent short or open condition, massage the wiring harness while watching the test equipment for a change. |
The numbers below refer to the step numbers on the diagnostic table.
DTCs P0753 and P0758 set if the power circuit is open.
This step tests the PCM and the wiring to the transmission 20-way connector.
This step tests circuit 418 for a short to battery power.
This step tests the circuit for correct resistance.
Step | Action | Value(s) | Yes | No | ||||||
---|---|---|---|---|---|---|---|---|---|---|
1 | Was the Powertrain On-Board Diagnostic (OBD) System Check performed? | -- | ||||||||
Important: Before clearing the DTCs, use the scan tool in order to record the Freeze Frame and Failure Records. Using the Clear Info function erases the Freeze Frame and Failure Records from the PCM. Are DTCs P0753 and P0758 also set? | -- | |||||||||
3 |
Was the condition found? | -- | ||||||||
4 |
Important: The condition that affects this circuit may exist in other connecting branches of the circuit. Refer to Power Distribution Schematics in Wiring Systems, for complete circuit distribution. Inspect circuit 1039 for a short to ground. Refer to General Electrical Diagnosis in Wiring Systems. Was the condition found? | -- | ||||||||
5 |
Important: The condition that affects this circuit may exist in other connecting branches of the circuit. Refer to Power Distribution Schematics in Wiring Systems, for complete circuit distribution. Inspect circuit 839 for a short to ground. Refer to General Electrical Diagnosis in Wiring Systems. Was the condition found? | -- | -- | |||||||
6 | Inspect circuit 1039 for an open. Refer to General Electrical Diagnosis in Wiring Systems. Was the condition found? | -- | ||||||||
7 | Inspect circuit 839 for an open. Refer to General Electrical Diagnosis in Wiring Systems. Was the condition found? | -- | -- | |||||||
8 |
Is the test lamp ON? | -- | ||||||||
9 |
Is the test lamp ON? | -- | ||||||||
10 | Inspect circuit 418 for a short to ground. Refer to General Electrical Diagnosis in Wiring Systems. Was the condition found? | -- | -- | |||||||
Using the scan tool, cycle the TCC PWM solenoid valve ON and OFF three times. Does the test lamp Cycle ON and OFF as commanded? | -- | |||||||||
12 | Is the test lamp always OFF? | -- | -- | |||||||
13 | Inspect circuit 418 for an open. Refer to General Electrical Diagnosis in Wiring Systems. Was the condition found? | -- | ||||||||
Connect a test lamp from terminal T to a good ground. Is the test lamp ON? | -- | |||||||||
15 | Inspect circuit 418 for a short to battery power. Refer to General Electrical Diagnosis in Wiring Systems. Was the condition found? | -- | -- | |||||||
Is the resistance within the specified range? | 10-15 ohms | |||||||||
17 | Is the resistance greater than the specified value? | 250 ohms | ||||||||
18 |
Refer to General Electrical Diagnosis in Wiring Systems. Was a condition found? | -- | ||||||||
19 | Measure the resistance from terminal T to a good ground. Is the resistance less than the specified value? | 1,000 ohms | ||||||||
20 | Inspect circuit 418 for a short to ground. Refer to General Electrical Diagnosis in Wiring Systems. Was the condition found? | -- | -- | |||||||
21 | Repair the wiring as necessary. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | -- | |||||||
22 | Replace the automatic transmission wiring harness. Refer to Unit Repair. Is the replacement complete? | -- | -- | |||||||
23 | Replace the TCC PWM solenoid valve. Refer to Control and Shift Solenoids Replacement. Is the replacement complete? | -- | -- | |||||||
24 | Replace the PCM. Refer to Powertrain Control Module Replacement/Programming in Engine Controls. Is the replacement complete? | -- | -- | |||||||
25 | Perform the following procedure in order to verify the repair:
Has the test run and passed? | -- | System OK |
The torque converter clutch pulse width modulation (TCC PWM) solenoid valve is a normally closed solenoid used to control the apply and release of the converter clutch. The PCM operates the solenoid with a negative duty cycle. When vehicle operating conditions are appropriate to apply the TCC, the PCM immediately increases the duty cycle to approximately 42%. The PCM then ramps the duty cycle to approximately 90% to achieve full TCC apply pressure. When the solenoid is commanded OFF, the PCM senses low voltage. When the solenoid is commanded ON, the PCM senses high voltage.
When the PCM detects a continuous open, short to ground or short to power in the TCC PWM solenoid valve circuit, then DTC P1860 sets. DTC P1860 is a type A DTC .
• | The system voltage is 8-18 volts. |
• | The engine has been running for more than 5 seconds, and is not in fuel cut off. |
• | The TCC PWM solenoid valve duty cycle is less than 10% or greater than 90%. |
• | The PCM detects an open, short to ground or a short to power on the TCC PWM solenoid valve circuit within 5 seconds. |
• | The PCM illuminates the malfunction indicator lamp (MIL). |
• | The PCM inhibits TCC engagement. |
• | The PCM freezes shift adapts from being updated. |
• | The PCM stores DTC P1860 in PCM history. |
• | The PCM turns OFF the MIL during the third consecutive trip in which the diagnostic test runs and passes. |
• | A scan tool clears the DTC from PCM history. |
• | The PCM clears the DTC from PCM history if the vehicle completes 40 warm-up cycles without an emission-related diagnostic fault occurring. |
• | The PCM cancels the DTC default actions when the fault no longer exists and the ignition switch is OFF long enough in order to power down the PCM. |
• | Inspect the wiring at the PCM, the transmission 20-way connector and the TCC PWM solenoid valve 2-way connector for the following conditions: |
- | A backed out terminal |
- | A damaged terminal |
- | Reduced terminal tension |
- | A chafed wire |
- | A broken wire inside the insulation |
- | Moisture intrusion |
- | Corrosion |
• | Ensure that the transmission fluid is at the proper level. |
• | When diagnosing for an intermittent short or open condition, massage the wiring harness while watching the test equipment for a change. |
The numbers below refer to the step numbers on the diagnostic table.
DTCs P0753 and P0758 set if the power circuit is open.
This step tests the PCM and the wiring to the transmission 20-way connector.
This step tests circuit 418 for a short to battery power.
This step tests the circuit for correct resistance.
Step | Action | Value(s) | Yes | No | ||||||
---|---|---|---|---|---|---|---|---|---|---|
1 | Was the Powertrain On-Board Diagnostic (OBD) System Check performed? | -- | ||||||||
Important: Before clearing the DTCs, use the scan tool in order to record the Freeze Frame and Failure Records. Using the Clear Info function erases the Freeze Frame and Failure Records from the PCM. Are DTCs P0753 and P0758 also set? | -- | |||||||||
3 |
Was the condition found? | -- | ||||||||
4 |
Important: The condition that affects this circuit may exist in other connecting branches of the circuit. Refer to Power Distribution Schematics in Wiring Systems, for complete circuit distribution. Inspect circuit 1039 for a short to ground. Refer to General Electrical Diagnosis in Wiring Systems. Was the condition found? | -- | ||||||||
5 |
Important: The condition that affects this circuit may exist in other connecting branches of the circuit. Refer to Power Distribution Schematics in Wiring Systems, for complete circuit distribution. Inspect circuit 839 for a short to ground. Refer to General Electrical Diagnosis in Wiring Systems. Was the condition found? | -- | -- | |||||||
6 | Inspect circuit 1039 for an open. Refer to General Electrical Diagnosis in Wiring Systems. Was the condition found? | -- | ||||||||
7 | Inspect circuit 839 for an open. Refer to General Electrical Diagnosis in Wiring Systems. Was the condition found? | -- | -- | |||||||
8 |
Is the test lamp ON? | -- | ||||||||
9 |
Is the test lamp ON? | -- | ||||||||
10 | Inspect circuit 418 for a short to ground. Refer to General Electrical Diagnosis in Wiring Systems. Was the condition found? | -- | -- | |||||||
Using the scan tool, cycle the TCC PWM solenoid valve ON and OFF three times. Does the test lamp Cycle ON and OFF as commanded? | -- | |||||||||
12 | Is the test lamp always OFF? | -- | -- | |||||||
13 | Inspect circuit 418 for an open. Refer to General Electrical Diagnosis in Wiring Systems. Was the condition found? | -- | ||||||||
Connect a test lamp from terminal T to a good ground. Is the test lamp ON? | -- | |||||||||
15 | Inspect circuit 418 for a short to battery power. Refer to General Electrical Diagnosis in Wiring Systems. Was the condition found? | -- | -- | |||||||
Is the resistance within the specified range? | 10-15 ohms | |||||||||
17 | Is the resistance greater than the specified value? | 250 ohms | ||||||||
18 |
Refer to General Electrical Diagnosis in Wiring Systems. Was a condition found? | -- | ||||||||
19 | Measure the resistance from terminal T to a good ground. Is the resistance less than the specified value? | 1,000 ohms | ||||||||
20 | Inspect circuit 418 for a short to ground. Refer to General Electrical Diagnosis in Wiring Systems. Was the condition found? | -- | -- | |||||||
21 | Repair the wiring as necessary. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | -- | |||||||
22 | Replace the automatic transmission wiring harness. Refer to Unit Repair. Is the replacement complete? | -- | -- | |||||||
23 | Replace the TCC PWM solenoid valve. Refer to Control and Shift Solenoids Replacement. Is the replacement complete? | -- | -- | |||||||
24 | Replace the PCM. Refer to Powertrain Control Module Replacement/Programming in Engine Controls. Is the replacement complete? | -- | -- | |||||||
25 | Perform the following procedure in order to verify the repair:
Has the test run and passed? | -- | System OK |