Table 1: | Shift Solenoid Valve State and Gear Ratio 4L60-E |
Table 2: | DTC P0753 1-2 Shift Solenoid Valve - Electrical |
The 1-2 Shift Solenoid Valve (1-2 SS Valve) controls the fluid flow acting on the 1-2 and 3-4 shift valve. The solenoid is a normally-open exhaust valve. The combination of the 2-3 Shift Solenoid Valve and the 1-2 SS Valve allows four different shifting combinations. The solenoid attaches to the control valve body within the transmission. Circuit 439 supplies ignition voltage directly to the 1-2 SS Valve. The PCM controls the solenoid by providing a ground path through circuit 1222.
When the PCM detects a continuous open or a short to ground in the 1-2 SS Valve circuit or the 1-2 SS Valve, then DTC P0753 sets. DTC P0753 is a type A DTC.
• | The ignition is ON. |
• | The system voltage is 10-17 volts. |
• | The PCM commands the solenoid ON and the voltage remains high (B+). |
• | The PCM commands the solenoid OFF and the voltage remains low (0 volts). |
• | All conditions met for 5 seconds |
• | The PCM commands maximum line pressure |
• | The PCM freezes shift adapts from being updated. |
• | If in hot mode, force the TCC on in 3rd and 4th gear when the brake is not applied and downshift is not requested. |
• | The PCM inhibits downshifts to 2nd when the speed is greater than 30 mph. |
• | The PCM illuminates the Malfunction Indicator Lamp (MIL) |
• | The PCM turns OFF the MIL after three consecutive ignition cycles 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. |
• | Inspect the wiring for any poor electrical connections at the PCM. Inspect the wiring at the TCC brake switch. Look 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 |
• | When diagnosing for an intermittent short or an open condition, massage the wiring harness while watching the test equipment for changes. |
• | An open feed circuit can set multiple DTCs. |
Gear | 1-2 Shift Solenoid | 2-3 Shift Solenoid | Gear Ratio |
---|---|---|---|
1 | ON | ON | 3.059:1 |
2 | OFF | ON | 1.625:1 |
3 | OFF | OFF | 1.000:1 |
4 | ON | OFF | 0.696:1 |
The numbers below refer to the Step numbers on the diagnostic table.
This step verifies that the 1-2 SS Valve and the Automatic Transmission Wiring Harness are functioning normally.
This step verifies that the ignition supplies power to the 1-2 SS Valve through the PCM IGN fuse.
This step verifies that the valve's resistance is within specifications.
Step | Action | Value(s) | Yes | No | ||||||
---|---|---|---|---|---|---|---|---|---|---|
1 | Was the Powertrain On-Board Diagnostic (OBD) System Check performed? | -- | Go to Powertrain On Board Diagnostic (OBD) System Check , Section 6 | |||||||
2 |
Important: Before clearing the DTCs, use the scan tool in order to record the Freeze Frame and Failure Records for reference. The Clear Info function will erase the data. | -- | ||||||||
3 |
Refer to Electrical Diagnosis, Section 8. Did you find and correct a problem? | -- | -- | |||||||
Using the scan tool, command the 1-2 SS Valve ON and OFF three times while listening to the bottom of the transmission pan (a stethoscope may be necessary). Did the solenoid click when commanded? | -- | |||||||||
5 | Inspect every connection at the PCM and at the transmission 20-way harness for the following conditions:
Did you find and correct a problem? | -- | Go to Diagnostic Aids | |||||||
Did the test lamp Illuminate? | -- | |||||||||
7 |
Important: Ground Pin R of the Jumper Harness. Does the test lamp illuminate when you command the solenoid valve ON, and turn OFF when you command the solenoid valve OFF? | -- | ||||||||
8 | Repair the open in the ignition feed circuit 439 to the 1-2 SS Valve. Refer to Electrical Diagnosis, Section 8. Did you find and correct a problem? | -- | -- | |||||||
9 | Monitor the test lamp. Was the test lamp OFF continuously? | -- | ||||||||
10 |
Did you find and correct a problem? | -- | ||||||||
11 | Was the test lamp illuminated continuously? | -- | -- | |||||||
12 |
Refer to Electrical Diagnosis, Section 8. Did you find and correct a problem? | -- | ||||||||
13 | Inspect the PCM connector for the following conditions:
Did you find and correct a problem? | -- | ||||||||
14 |
Are both readings greater than the specified value? | 250 kohms | ||||||||
15 |
Is the resistance within the specified range? | 19-31ohms | Go to Diagnostic Aids | |||||||
Is the resistance within the specified range? | 19-31ohms | |||||||||
17 |
Refer to Electrical Diagnosis, Section 8. Did you find and correct a problem? | -- | -- | |||||||
18 |
Are both readings greater than the specified value? | 250 kohms | ||||||||
19 |
Refer to Electrical Diagnosis, Section 8. Did you find and correct a problem? | -- | -- | |||||||
20 | Replace the 1-2 SS Valve. Refer to 1-2 Shift Solenoid Valve Replacement, in On-Vehicle Service. Is the replacement complete? | -- | -- | |||||||
21 | Replace the PCM. Refer to Powertrain Control Module Replacement/Programming , Section 6. Is the replacement complete? | -- | -- | |||||||
22 |
Has the test run and passed? | -- | System OK |
Table 1: | Shift Solenoid Valve State and Gear Ratio 4L60-E |
Table 2: | DTC P0753 1-2 Shift Solenoid Valve - Electrical |
The 1-2 Shift Solenoid Valve (1-2 SS Valve) controls the fluid flow acting on the 1-2 and 3-4 shift valve. The solenoid is a normally-open exhaust valve. The combination of the 2-3 Shift Solenoid Valve and the 1-2 SS Valve allows four different shifting combinations. The solenoid attaches to the control valve body within the transmission. Circuit 439 supplies ignition voltage directly to the 1-2 SS Valve. The PCM controls the solenoid by providing a ground path through circuit 1222.
When the PCM detects a continuous open or a short to ground in the 1-2 SS Valve circuit or the 1-2 SS Valve, then DTC P0753 sets. DTC P0753 is a type A DTC.
• | The ignition is ON. |
• | The system voltage is 10-17 volts. |
• | The PCM commands the solenoid ON and the voltage remains high (B+). |
• | The PCM commands the solenoid OFF and the voltage remains low (0 volts). |
• | All conditions met for 5 seconds |
• | The PCM commands maximum line pressure. |
• | The PCM freezes shift adapts from being updated. |
• | The PCM illuminates the Malfunction Indicator Lamp (MIL). |
• | The PCM turns OFF the MIL after three consecutive ignition cycles 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. |
• | Inspect the wiring for any poor electrical connections at the PCM. Inspect the wiring at the TCC brake switch. Look 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 |
• | When diagnosing for an intermittent short or an open condition, massage the wiring harness while watching the test equipment for a change. |
• | An open feed circuit can set multiple DTCs. |
Gear | 1-2 Shift Solenoid | 2-3 Shift Solenoid | Gear Ratio |
---|---|---|---|
1 | ON | ON | 3.059:1 |
2 | OFF | ON | 1.625:1 |
3 | OFF | OFF | 1.000:1 |
4 | ON | OFF | 0.696:1 |
The numbers below refer to the step numbers on the diagnostic chart.
This step verifies that the 1-2 SS Valve and the Automatic Transmission Wiring Harness are functioning normally.
This step verifies that the ignition supplies power to the 1-2 SS Valve through the PCM IGN fuse.
This step verifies that the valve's resistance is within specifications.
Step | Action | Value(s) | Yes | No | ||||||
---|---|---|---|---|---|---|---|---|---|---|
1 | Was the Powertrain On-Board Diagnostic (OBD) System Check performed? | -- | Go to Powertrain On Board Diagnostic (OBD) System Check , Section 6 | |||||||
2 |
Important: Before clearing the DTCs, use the scan tool in order to record the Freeze Frame and Failure Records for reference. The Clear Info function will erase the data. | -- | ||||||||
3 |
Refer to Electrical Diagnosis, Section 8. Did you find and correct a problem? | -- | -- | |||||||
Using the scan tool, command the 1-2 SS Valve ON and OFF three times while listening to the bottom of the transmission pan (a stethoscope may be necessary). Did the solenoid click when commanded? | -- | |||||||||
5 | Inspect every connection at the PCM and at the transmission 20-way harness for the following conditions:
Did you find and correct a problem? | -- | Go to Diagnostic Aids | |||||||
Did the test lamp Illuminate? | -- | |||||||||
7 |
Does the test lamp illuminate when you command the solenoid valve ON, and turn OFF when you command the solenoid valve OFF? | -- | ||||||||
8 | Repair the open or short to ground in the ignition feed circuit 439 to the 1-2 SS Valve. Refer to Electrical Diagnosis, Section 8. Did you find and correct a problem? | -- | -- | |||||||
9 | Monitor the test lamp. Was the test lamp OFF continuously? | -- | ||||||||
10 |
Did you find and correct a problem? | -- | ||||||||
11 | Was the test lamp illuminated continuously? | -- | -- | |||||||
12 |
Refer to Electrical Diagnosis, Section 8. Did you find and correct a problem? | -- | ||||||||
13 | Inspect the PCM connector for the following conditions:
Did you find and correct a problem? | -- | ||||||||
14 |
Are both readings greater than the specified value? | 250kohms | ||||||||
15 |
Is the resistance within the specified range? | 19-31ohms | Go to Diagnostic Aids | |||||||
Is the resistance within the specified range? | 19-31ohms | |||||||||
17 |
Refer to Electrical Diagnosis, Section 8. Did you find and correct a problem? | -- | -- | |||||||
18 |
Are both readings greater than the specified value? | 250kohms | ||||||||
19 |
Refer to Electrical Diagnosis, Section 8. Did you find and correct a problem? | -- | -- | |||||||
20 | Replace the 1-2 SS Valve. Refer to 1-2 Shift Solenoid Valve Replacement, in On-Vehicle Service. Is the replacement complete? | -- | -- | |||||||
21 | Replace the PCM. Refer to Powertrain Control Module Replacement/Programming , Section 6 Is the replacement complete? | -- | -- | |||||||
22 |
Has the test run and passed? | -- | System OK |