Circuit Description
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 high voltage. When the solenoid is commanded ON, the PCM senses low voltage.
When the PCM detects a continuous open, short to ground or short to voltage in the TCC PWM solenoid valve circuit, then DTC P1860 sets. DTC P1860 is a type A DTC .
Conditions for Running the 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 70%. |
Conditions for Setting the DTC
The PCM detects an open, short to ground or a short to voltage on the TCC PWM solenoid valve circuit within 4.3 seconds.
Action Taken When the DTC Sets
| • | The PCM illuminates the malfunction indicator lamp (MIL). |
| • | The PCM inhibits TCC engagement. |
| • | The PCM freezes shift adapts from being updated. |
| • | The PCM records the operating conditions when the Conditions for Setting the DTC are met. The PCM stores this information as Freeze Frame and Failure Records. |
| • | The PCM stores DTC P1860 in PCM history. |
Conditions for Clearing the MIL/DTC
| • | The PCM turns OFF the MIL during the third consecutive trip in which the diagnostic test runs and passes. |
| • | A scan tool can clear the MIL/DTC. |
| • | 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/or the ignition switch is OFF long enough in order to power down the PCM. |
Diagnostic Aids
| • | Inspect the connectors at the PCM, the TCC PWM solenoid valve and all other circuit connecting points for an intermittent condition. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. |
| • | Inspect the circuit wiring for an intermittent condition. Refer to Testing for Electrical Intermittents in Wiring Systems. |
| • | Ensure that the transmission fluid is at the proper level. |
| • | Ensure the wiring harness is not stretched too tightly or other components are pressing on the connector body. Also, inspect for proper clearance to any other components and wiring. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
This step tests the PCM and the wiring to the AT inline 20-way connector.
-
This step tests the control circuit for a short to voltage.
-
This step tests the circuit for correct resistance.
Step | Action | Value(s) | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
1 | Did you perform the Powertrain Diagnostic System Check? | -- | Go to Powertrain On Board Diagnostic (OBD) System Check (2.2L) or Powertrain On Board Diagnostic (OBD) System Check (2.4L) | |||||||
2 |
Important: Before clearing the DTC, use the Scan Tool in order to record the Failure Records. Using the Clear Info function erases the Failure Records from the PCM. Is DTC P0753 or P0758 also set? | -- | ||||||||
3 |
Refer to Wiring Repairs in Wiring Systems. Did you find the condition? | -- | ||||||||
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. Test the power feed circuit (CKT 439) of the TCC PWM solenoid valve for a short to ground between the fuse block and the AT inline 20-way connector. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | ||||||||
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. Test the power feed circuit (CKT 839) of the TCC PWM solenoid valve for a short to ground between the AT inline 20-way connector and the TCC PWM solenoid valve. Refer to Circuit Testing in Wiring Systems. Did you find the condition? | -- | -- | |||||||
6 | Test the power feed circuit (CKT 439) of the TCC PWM solenoid valve for an open between the fuse block and the AT inline 20-way connector. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | ||||||||
7 | Test the power feed circuit (CKT 839) of the TCC PWM solenoid valve for an open between the AT inline 20-way connector and the TCC PWM solenoid valve. Refer to Circuit Testing in Wiring Systems. Did you find the condition? | -- | -- | |||||||
8 |
Refer to Automatic Transmission Inline Harness Connector End View . Is the test lamp ON? | -- | ||||||||
9 |
Is the test lamp ON? | -- | ||||||||
10 | Test the control circuit (CKT 418) of the TCC PWM solenoid valve for a short to ground between the PCM connector C2 and the AT inline 20-way connector. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | -- | |||||||
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 | Test the control circuit (CKT 418) of the TCC PWM solenoid valve for an open between the PCM connector C2 and the AT inline 20-way connector. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | ||||||||
Connect a test lamp from terminal T of the J 44152 to a good ground. Refer to Automatic Transmission Inline Harness Connector End View . Is the test lamp ON? | -- | |||||||||
15 | Test the control circuit (CKT 418) of the TCC PWM solenoid valve for a short to voltage between the PCM connector C2 and the AT inline 20-way connector. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | -- | |||||||
Refer to Automatic Transmission Inline Harness Connector End View . Is the resistance within the specified range? | 10-15 ohms | |||||||||
17 | Is the resistance greater than the specified value? | 250 ohms | ||||||||
18 |
Refer to Circuit Testing in Wiring Systems. Did you find a condition? | -- | ||||||||
19 | Measure the resistance from terminal T of the J 44152 to a good ground. Refer to Automatic Transmission Inline Harness Connector End View . Is the resistance less than the specified value? | 1000 ohms | ||||||||
20 | Test the control circuit (CKT 418) of the TCC PWM solenoid valve for a short to ground between the AT inline 20-way connector and the TCC PWM solenoid valve. Refer to Circuit Testing in Wiring Systems. Did you find a condition? | -- | -- | |||||||
21 | Replace the automatic transmission wiring harness. Refer to Transmission Overhaul in the 4T40-E/4T45-E section of the Transmission Unit Repair Manual. Did you complete the replacement? | -- | -- | |||||||
22 | Replace the TCC PWM solenoid valve. Refer to Control and Shift Solenoids Replacement. Did you complete the replacement? | -- | -- | |||||||
23 | Replace the PCM. Refer to Powertrain Control Module Replacement/Programming (2.2L) or Powertrain Control Module Replacement/Programming (2.4L) in Engine Controls. Did you complete the replacement? | -- | -- | |||||||
24 | Perform the following procedure in order to verify the repair:
Has the test run and passed? | -- | System OK |
