Automatic Transmission Wiring Harness Check. Chevrolet Tahoe

For 1990-2009 cars only

Makes 🢒 Chevrolet 🢒 1997 🢒 Tahoe - 2WD 🢒 Transmission/Transaxle 🢒 Automatic Transmission - 4L80-E 🢒 Automatic Transmission Wiring Harness Check

Important: The Automaitc Transmission Wiring Harness Assembly Check cannot be used for checking the Automatic Transmission Fluid Presure Manual Valve Position Switch (TFP Val. Position Sw.) circuit. Refer to Automatic Transmission Fluid Pressure Manual Valve Position Switch Resistance Check for those circuits.

4L80-E Transmission Internal Wiring Harness Check

Step

Action

Value(s)

Yes

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

Is the resistance within the values indicated?

19-24ohms @ 20°C (68°F)

24-31ohms @ 100°C

(212°F)

Go to Step 3

Go to Step 2

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

Is the resistance within the values indicated?

19-24ohms @ 20°C (68°F)

24-31ohms @ 100°C

(212°F)

Go to Step 12

Go to Step 14

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

Is the resistance within the values indicated?

19-24ohms @ 20°C (68°F)

24-31ohms @ 100°C

(212°F)

Go to Step 5

Go to Step 4

Disconnect the 2-3 Shift Solenoid Valve (2-3 SS Valve) from the A/T Wiring Harness Assy.
Using the DVOM, measure the resistance of the 2-3 SS Valve.

Is the resistance within the values indicated?

19-24ohms @ 20°C (68°F)

24-31ohms @ 100°C

(212°F)

Go to Step 12

Go to Step 14

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

Is the resistance within the values indicated?

10-11ohms @ 20°C (68°F)

13-15ohms @ 100°C (212°F)

Go to Step 7

Go to Step 6

Disconnect the Torque Converter Clutch Pulse Width Modulation Solenoid Valve (TCC PWM Sol. Valve) from the A/T Wiring Harness Assy.
Using the DVOM, measure the resistance of the TCC PWM Sol. Valve.

Is the resistance within the values indicated?

10-11ohms @ 20°C (68°F)

13-15ohms @ 100°C (212°F)

Go to Step 12

Go to Step 14

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

Is the resistance within the values indicated?

3-5ohms @ 20°C (68°F)

4-7ohms @ 100°C (212°F)

Go to Step 9

Go to Step 8

Disconnect the Pressure Control Solenoid Valve (PC Sol. Valve) from the A/T Wiring Harness Assy.
Using the DVOM, measure the resistance of the PC Sol. Valve.

Is the resistance within the values indicated?

3-5ohms @ 20°C (68°F)

4-7ohms @ 100°C (212°F)

Go to Step 12

Go to Step 14

Measure the resistance between terminals L and M (Transmission Fluid Temperature Sensor).

Is the resistance within the values indicated?

3333-3689ohms @ 20°C (68°F)

167-189ohms @ 100°C (212°F)

Go to Step 10

Go to Step 12

Measure the resistance from terminals A, B, C, D, E, L, M, and S of the A/T Wiring Harness Assy. at the transmission 20-way connector to the transmission case.

Is the resistance measured greater than the value indicated?

250kohms

No problem found. Exit table

Go to Step 13

Disconnect the A/T Wiring Harness Assy. from all the components.
Measure the resitance from all the components terminals to the transmission case.

Is the resistance measured greater than the value indicated?

250kohms

Go to Step 12

Go to Step 14

Inspect for high resitance or a shorted condition:

•	Inspect the A/T Wiring Harness Assy. for poor electrical connections at the transmission 20-way connector and at the component connectors.

•	Look for possible bent, backed out, deformed, or damaged terminals.

•	Inspect for weak terminal tension.

•	Inspect for chafed wire that could short to bare metal or other wiring.

•	If diagnosing for a possible intermittent condition, move or massage the A/T Wiring Harness Assy. while observing the test equipment for a change.

Was high resistance or a shorted condition found?

Verify the repair and go to Step 1

Go to Step 13

Replace the A/T Wiring Harness Assy.

Is the replacement complete?

Verify the repair and go to step 1

Replace the faulty component.

is the replacement complete?

Verify the repair go to step 1