DTC P1860 TCC PWM Solenoid Circuit Electrical 3.1L Vin M Only
Circuit Description
The Torque Converter Clutch Pulse Width Modulation Solenoid Valve (TCC PWM Sol. Valve) controls the fluid pressure to the converter clutch regulator valve, thereby controlling converter clutch apply pressure.
A fused circuit provides ignition voltage to the solenoid. An Output Driver Module (ODM), in the PCM, provides the ground to energize the solenoid. The solenoid valve is modulated by the PCM, varying the duty cycle. At 0% duty cycle the torque converter clutch applies at maximum capacity. At 100% duty cycle the torque converter clutch applies at minimum capacity.
When the PCM detects a continuous open, or short to ground in the TCC PWM Sol. circuit, then DTC P1860 sets. DTC P1860 is a type A DTC.
Conditions for Setting the DTC
| • | System voltage is 10-16 volts. |
| • | The engine speed is more than 500 RPM for 5 seconds. |
| • | Not in fuel shut off. |
| • | The PCM commands the solenoid below 10%, and above 90% duty cycle, and the voltage on circuit 418 is outside the calibrated limits. |
Action Taken When the DTC Sets
| • | The PCM illuminates the Malfunction Indicator Lamp (MIL). |
| • | The PCM inhibits TCC operation. |
| • | The PCM inhibits 4th gear if the transmission is in the hot mode. |
Conditions for Clearing the MIL/DTC
| • | The PCM turns OFF the MIL after three consecutive trips without a failure reported. |
| • | A scan tool can clear the DTC from the PCM history. The PCM clears the DTC from the PCM history if the vehicle completes 40 warm-up cycles without a failure reported. |
| • | The PCM cancels the DTC default actions when the fault no longer exists and the ignition is OFF long enough in order to power down the PCM. |
Diagnostic Aids
| • | Inspect the wiring at the PCM, the transmission connector, TCC PWM solenoid connector and all other circuit connecting points for the following conditions: |
| - | A bent terminal |
| - | A backed out terminal |
| - | A damaged terminal |
| - | Poor terminal tension |
| - | A chafed wire |
| - | A broken wire inside the insulation |
| - | Moisture intrusion |
| - | Corrosion |
| • | When diagnosing for an intermittent short or open condition, massage the wiring harness while watching the test equipment for a change. |
| • | Ensure that the transmission fluid is at the proper level. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
This step isolates the engine harness from the transmission harness.
-
This step verifies that circuit 418 is not open or shorted to power.
-
This step verifies that the solenoid is not open or shorted across its windings, and the transmission harness is not open or shorted.
Step | Action | Value(s) | Yes | No | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1 | Was the Powertrain On-Board Diagnostic (OBD) System Check performed? | -- | ||||||||||||||
2 |
Important: Before clearing the DTCs, use the scan tool in order to record the Freeze Frame and Failure Records for reference. Using the Clear Info function will erase the stored Freeze Frame and Failure Records from the PCM. Did either reading flicker No/Yes/No? | -- | Go to Diagnostic Aids | |||||||||||||
Is the test lamp OFF? | -- | |||||||||||||||
4 | Inspect circuit 418 of engine harness for an open. Refer to General Electrical Diagnosis in Wiring Systems. Was a condition found and corrected? | -- | ||||||||||||||
Important: When the Scan Tool is used to command the TCC PWM (Control) Solenoid ON, the Scan Tool will indicate 99% duty cycle. The solenoid will be de-energized (test lamp OFF). The scan tool will indicate 0% duty cycle when the TCC Duty Cycle (PWM Solenoid) is commanded OFF. The solenoid will be energized (test lamp ON). Does the solenoid cycle ON and OFF as commanded? | -- | |||||||||||||||
6 | Inspect engine harness circuit 418 for a short to ground. Refer to General Electrical Diagnosis in Wiring Systems. Was a condition found and corrected? | -- | ||||||||||||||
7 | Inspect engine harness circuit 418 for a short to power. Refer to General Electrical Diagnosis in Wiring Systems. Was a condition found and corrected? | -- | ||||||||||||||
Is the measured resistance within the specified range? | 10 ohms to 15 ohms | |||||||||||||||
9 | Is the resistance greater than the specified value? | 15 ohms | ||||||||||||||
10 | Inspect the RED wire circuit 839 and the BLK wire circuit 418 of the transmission harness for an open. Refer to General Electrical Diagnosis in Wiring Systems. Was a condition found? | -- | ||||||||||||||
11 | Replace the Automatic Transmission Wiring Harness. Refer to Solenoids and Wiring Harness Replacement. Is the replacement complete? | -- | -- | |||||||||||||
12 | Connect a J 39200 Digital Multimeter (DMM) from terminal C of the jumper to ground. Is the measured resistance less than the specified value? | 100 ohms | ||||||||||||||
13 | Inspect the BLK wire circuit 418 of the transmission harness for a short to ground. Refer to General Electrical Diagnosis in Wiring Systems. Was a condition found? | -- | -- | |||||||||||||
14 | Replace the Automatic Transmission Wiring Harness. Refer to Solenoids and Wiring Harness Replacement. Is the replacement complete? | -- | -- | |||||||||||||
15 | Replace the TCC PWM Sol. Valve. Refer to Solenoids and Wiring Harness Replacement. Is the replacement complete? | -- | -- | |||||||||||||
16 | Inspect PCM connector C2 (Clear) for bent, damaged or backed out connector pins. Was a condition found and corrected? | -- | ||||||||||||||
17 | Replace the PCM. Refer to Powertrain Control Module Replacement/Programming in Engine Controls. Is the replacement complete? | -- | -- | |||||||||||||
18 | Perform the following procedure to verify your repair:
Has the test run and passed? | -- | System OK |
