GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 1997 🢒 Savana 🢒 Engine 🢒 Engine Controls - 5.0L, 5.7L, and 7.4L 🢒 Automatic Transmission Wiring Harness Check

Automatic Transmission Wiring Harness Check

Step

Action

Value(s)

Yes

No

Important: This procedure cannot be used for checking the Automatic Transmission Fluid Pressure Manual Valve Position Switch (TFP Val. Position Sw.) circuit, or the Automatic Transmission Fluid Temperature (TFT) Sensor circuit. Refer to the Transmission Fluid Pressure Manual Valve Position Switch Resistance Check , for those circuits.

1
  1. Install the J 39775 Jumper Harness on the transmission side of the 20-way connector.
  2. Using a J 39200 Digital Multimeter (DMM) and a J 35616-A Connector Test Adapter Kit, measure the resistance between terminals A and E (1-2 Shift Solenoid Valve).

Is the resistance within the specified range?

19-24 ohms @ 20°C (68°F)

24-31 ohms @ 100°C (212°F)

Go to Step 3

Go to Step 2

2
  1. Disconnect the 1-2 Shift Solenoid Valve (1-2 SS Valve) from the Automatic Transmission Wiring Harness Assembly (A/T Wiring Harness Assembly).
  2. Using the J 39200 DMM, measure the resistance of the 1-2 SS Valve.

Is the resistance within the specified range?

19-24 ohms @ 20°C (68°F)

24-31 ohms @ 100°C (212°F)

Go to Step 14

Go to Step 16

3

Measure the resistance between terminals B and E (2-3 Shift Solenoid Valve).

Is the resistance within the specified range?

19-24 ohms @ 20°C (68°F)

24-31 ohms @ 100°C (212°F)

Go to Step 5

Go to Step 4

4
  1. Disconnect the 2-3 Shift Solenoid Valve (2-3 SS Valve) from the A/T Wiring Harness Assembly.
  2. Using the J 39200 DMM, measure the resistance of the 2-3 SS Valve.

Is the resistance within the specified range?

19-24 ohms @ 20°C (68°F)

24-31 ohms @ 100°C (212°F)

Go to Step 14

Go to Step 16

5

Measure the resistance between terminals T and E (Torque Converter Clutch Solenoid Valve).

Is the resistance within the specified range?

21-26 ohms @ 20°C (68°F)

26-33 ohms @ 100°C (212°F)

Go to Step 6

Go to Step 14

6

Measure the resistance between terminals U and E (Torque Converter Clutch Pulse Width Modulation Solenoid Valve).

Is the resistance within the specified range?

10-11 ohms @ 20°C (68°F)

13-15 ohms @ 100°C (212°F)

Go to Step 8

Go to Step 7

7
  1. Disconnect the TCC PWM Sol. Valve from the A/T Wiring Harness Assembly.
  2. Using the J 39200 DMM, measure the resistance of the TCC PWM Sol. Valve.

Is the resistance within the specified range?

10-11 ohms @ 20°C (68°F)

13-15 ohms @ 100°C (212°F)

Go to Step 14

Go to Step 16

8

Measure the resistance between terminals S and E (3-2 Shift Solenoid Valve Assembly).

Is the resistance within the specified range?

20-24 ohms @ 20°C (68°F)

29-32 ohms @ 100°C (212°F)

Go to Step 10

Go to Step 9

9
  1. Disconnect the 3-2 Shift Solenoid Valve Assembly (3-2 SS Valve Assy.) from the A/T Wiring Harness Assembly.
  2. Using the J 39200 DMM, measure the resistance of the 3-2 SS Valve Assy.

Is the resistance within the specified range?

20-24 ohms @ 20°C (68°F)

29-32 ohms @ 100°C (212°F)

Go to Step 14

Go to Step 16

10

Measure the resistance between terminals C and D (Pressure Control Solenoid Valve).

Is the resistance within the specified range?

3-5 ohms @ 20°C (68°F)

4-7 ohms @ 100°C (212°F)

Go to Step 12

Go to Step 11

11
  1. Disconnect the Pressure Control Solenoid Valve (PC Sol. Valve) from the A/T Wiring Harness Assembly.
  2. Using the J 39200 DMM, measure the resistance of the PC Sol. Valve.

Is the resistance within the specified range?

3-5 ohms @ 20°C (68°F)

4-7 ohms @ 100°C (212°F)

Go to Step 14

Go to Step 16

12

Using the J 39200 DMM and the J 35616-A Connector Test Adapter Kit, measure the resistance from terminals A, B, C, D, E, S, T and U of the A/T Wiring Harness Assembly at the transmission 20-way connector to the transmission case.

Is the resistance more than the specified value?

250 K ohms

System OK, exit the table

Go to Step 13

13
  1. Disconnect the A/T Wiring Harness Assembly from all the components.
  2. Measure the resistance from all the component terminals to the transmission case.

Is the resistance more than the specified value?

250 K ohms

Go to Step 14

Go to Step 16

14

Inspect for high resistance or a short.

    • Inspect the A/T Wiring Harness Assembly at the transmission 20-way connector, and the component connectors for the following conditions:
       - Poor electrical connections
       - A backed out terminal
       - A damaged terminal
       - A bent terminal
       - Poor terminal tension
       - A chafed wire that could short to bare metal or other wiring
       - A broken wire inside the insulation
       - Moisture intrusion
       - Corrosion
    • If diagnosing for a possible intermittent condition, move or massage the A/T Wiring Harness Assembly while observing the test equipment for a change.

Did you find a high resistance or a short?

--

Verify the repair. Go to Step 1

Go to Step 15

15

Replace the Automatic Transmission Wiring Harness Assembly (A/T Wiring Harness Assembly).

Refer to TCC PWM Solenoid, TCC Solenoid, and Wiring Harness Replacement.

Is the replacement complete?

--

Verify the repair. Go to Step 1

--

16

Replace the faulty component.

Is the replacement complete?

--

Verify the repair. Go to Step 1

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