This diagnostic procedure supports DTC P0976 3-2 Shift Solenoid (SS) Control Circuit Low Voltage
The 2-3 shift solenoid (SS) valve controls the fluid flow acting on the 2-3 shift valves. The solenoid is a normally-open exhaust valve. With the 1-2 SS valve, the 2-3 SS valve allows four different shifting combinations. The solenoid attached to the control valve body within the transmission. The 2-3 SS receives voltage through the ignition 1 voltage circuit (circuit 339). The transmission control module (TCM) controls the solenoid by providing a ground path on the 2-3 SS valve control circuit (circuit 1223).
When the TCM detects a continuous open or short to ground in the 2-3 SS valve circuit, then DTC P0976 sets. DTC P0976 is a type A DTC.
Refer to Automatic Transmission Controls Schematics , Automatic Transmission Inline 20-Way Connector End View, Automatic Transmission Internal Connector End Views , Automatic Transmission Control Module Connector End Views , and Automatic Transmission Related Connector End Views to aid in diagnosis.
• | The engine run time is greater than 5 seconds. |
• | The 2-3 SS is commanded on. |
DTC P0976 sets when either of the following conditions occurs for 4.3 seconds:
• | The TCM detects an open in the 2-3 shift solenoid valve circuit when the 2-3 SS is commanded on. |
• | The TCM detects a short to ground in the 2-3 shift solenoid valve circuit when the 2-3 SS is commanded on. |
• | The TCM requests the ECM to illuminate the check powertrain icon. |
• | The TCM commands maximum line pressure. |
• | The TCM inhibits 3-2 shift if vehicle speed is less than 40 km/h. |
• | The TCM freezes transmission adaptive functions. |
• | At the time of the first failure, the TCM records the operating conditions when the conditions for setting the DTC are met. The TCM stores this information as a Failure Record. |
• | At the time of the first failure, the ECM records the operating conditions when the conditions for setting the DTC are met. The ECM stores this information as a Freeze Frame. |
• | The TCM stores DTC P0976 in TCM history. |
• | The ECM turns off the check powertrain icon after the fourth consecutive drive trip in which the TCM does not send a check powertrain icon illumination request. |
• | Tech 2 can clear the DTC. |
• | The TCM clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without a non-emission related diagnostic fault occurring. |
• | The TCM cancels the DTC default actions when the ignition is off long enough in order to power down the TCM |
The following numbers refer to the step numbers on the diagnostic table:
Step | Action | Yes | No | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1 | Has the Diagnostic System Check been performed? | Go to Step 2 | |||||||||||
2 |
Important: Before clearing the DTC, use the Tech 2 Freeze Frame/Failure Record in order to record the transmission parameters at the time the DTC set. Using Tech 2 to clear the DTC(s) erases the Freeze Frame/Failure Record records from the TCM. Transmission / Automatic Transmission / Diagnostic Trouble Codes / Freeze Frame. Diagnostic Trouble Codes / Clear Engine and Transmission DTCs. Are any of the following DTCs also set?
| Go to Step 3 | Go to Step 4 | ||||||||||
3 | Inspect fuse F8 and check if it is blown, refer to Section 12O Fuses, Relays and Wiring Harnesses. Is the fuse blown? | Replace the fuse Go to Step 12 | Go to Step 5 | ||||||||||
4 |
Automatic Transmission / Miscellaneous Tests / Shift Solenoid B. Data Display / 2-3 Shift Data. Does Tech 2 display the Shift Solenoid B Circuit as Okay ? | Check for an intermittent fault in the circuit, refer to Testing for Intermittent Conditions and Poor Connections | Go to Step 5 | ||||||||||
5 |
Important: Additional DTCs may set Does the test lamp illuminate? | Go to Step 6 | Go to Step 15 | ||||||||||
6 |
Automatic Transmission / Miscellaneous Tests / Shift Solenoid B. Does the test lamp turn on and off with each command? | Go to Step 8 | Go to Step 7 | ||||||||||
7 | Is the test lamp always illuminates? | Go to Step 16 | Go to Step 17 | ||||||||||
8 |
Does the multimeter display 19-31 Ω? | Go to Step 9 | Go to Step 10 | ||||||||||
9 | Using a multimeter set to measure resistance, probe between:
Does the multimeter display greater than 250 kΩ in both instances? | Check for an intermittent fault in the circuit, refer to Testing for Intermittent Conditions and Poor Connections | Go to Step 11 | ||||||||||
10 |
Does the multimeter display 19-31 Ω? | Replace the control valve body wiring harness, refer to Torque Converter Clutch Pulse Width Modulation Solenoid, Torque Converter Clutch Solenoid, and Wiring Harness. Go to Step 19 | Replace the 2-3 SS, refer to Torque Converter Clutch Pulse Width Modulation Solenoid, Torque Converter Clutch Solenoid, and Wiring Harness Go to Step 19 | ||||||||||
11 |
Does the multimeter display 250 kΩ in both instances? | Replace the control valve body wiring harness, refer to Torque Converter Clutch Pulse Width Modulation Solenoid, Torque Converter Clutch Solenoid, and Wiring Harness Go to Step 19 | Replace the 2-3 shift solenoid, refer to Torque Converter Clutch Pulse Width Modulation Solenoid, Torque Converter Clutch Solenoid, and Wiring Harness Go to Step 19 | ||||||||||
12 | Test circuit 339 for a short to ground between connector X121 - X1 pin E and the splice. Did you find and correct the condition? | Go to Step 19 | Go to Step 13 | ||||||||||
13 |
Did you find a short ground condition? | Replace the control valve body wiring harness, refer to Torque Converter Clutch Pulse Width Modulation Solenoid, Torque Converter Clutch Solenoid, and Wiring Harness Go to Step 19 | Go to Step 14 | ||||||||||
14 |
Did you complete the replacement? | Go to Step 19 | -- | ||||||||||
15 | Test circuit 339 for an open circuit between connector X121 - X1 pin E and the splice. Did you find and correct the condition? | Go to Step 19 | -- | ||||||||||
16 | Using a multimeter, test circuit 1223 for a short to ground. Did you find and correct the condition? | Go to Step 19 | Go to Step 20 | ||||||||||
17 | Using a multimeter, test circuit 1223 for an open circuit. Did you find and correct the condition? | Go to Step 19 | Go to Step 20 | ||||||||||
18 | Replace the TCM, refer to Transmission Control Module Replacement. Did you complete the replacement? | Go to Step 19 | -- | ||||||||||
19 | Perform the following procedure in order to verify the repair:
Diagnostic Trouble Codes / Clear Engine and Transmission DTCs. Data Display / 2-3 Shift Data.
Diagnostic Trouble Codes / Read DTC Information. Has DTC P0976 set? | Go to Step 2 | Go to Step 20 | ||||||||||
20 | On Tech select: Diagnostic Trouble Codes / Read DTC Information. Does Tech 2 display any DTCs you have not diagnosed? | Refer to Scan Tool Data List | System OK | ||||||||||
When all diagnosis and repairs are completed, check the system for correct operation. |