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For 1990-2009 cars only

Automatic Transmission Wiring Harness Check 1999 V Car 4L30-E

Step

Action

Value(s)

Yes

No

1

  1. Disconnect the transmission main case 7-way connector.
  2. Using a J 39200 digital multimeter (DMM) and a J 35616-A connector test adapter kit, measure the resistance between terminals C and D (1-2/3-4 shift solenoid valve).

Is the resistance within the specified range?

17.5-18.5 ohms @ 20°C (68°F)

21.0-21.1 ohms @ 70°C (158°F)

Go to Step 3

Go to Step 2

2

  1. Disconnect the 1-2/3-4 shift solenoid (SS) valve from the automatic transmission wiring harness assembly.
  2. Using the J 39200 DMM, measure the resistance of the 1-2/3-4 SS valve.

Is the resistance within the specified range?

17.5-18.5 ohms @ 20°C (68°F)

21.0-21.1 ohms @ 70°C (158°F)

Go to Step 12

Go to Step 14

3

Measure the resistance between terminals A and D (2-3 shift solenoid valve).

Is the resistance within the specified range?

17.5-18.5 ohms @ 20°C (68°F)

21.0-21.1 ohms @ 70°C (158°F)

Go to Step 5

Go to Step 4

4

  1. Disconnect the 2-3 shift solenoid (SS) valve from the automatic transmission 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?

17.5-18.5 ohms @ 20°C (68°F)

21.0-21.1 ohms @ 70°C (158°F)

Go to Step 12

Go to Step 14

5

Measure the resistance between terminals B and D (band apply PWM solenoid valve).

Is the resistance within the specified range?

9.5-10.5 ohms @ 20°C (68°F)

11.5-12.5 ohms @ 70°C (158°F)

Go to Step 6

Go to Step 12

6

  1. Disconnect the transmission adapter case 4-way connector.
  2. Measure the resistance between terminals A and D (torque converter clutch solenoid valve).

Is the resistance within the specified range?

17.5-18.5 ohms @ 20°C (68°F)

21.0-21.1 ohms @ 70°C (158°F)

Go to Step 8

Go to Step 7

7

  1. Disconnect the TCC solenoid valve from the automatic transmission wiring harness assembly.
  2. Using the J 39200 DMM, measure the resistance of the TCC solenoid valve.

Is the resistance within the specified range?

17.5-18.5 ohms @ 20°C (68°F)

21.0-21.1 ohms @ 70°C (158°F)

Go to Step 12

Go to Step 14

8

Measure the resistance between terminals B and C (pressure control solenoid valve).

Is the resistance within the specified range?

3.5-4.6 ohms @ 20°C (68°F)

4.2-5.5 ohms @ 70°C (158°F)

Go to Step 10

Go to Step 9

9

  1. Disconnect the pressure control (PC) solenoid valve from the automatic transmission wiring harness assembly.
  2. Using the J 39200 DMM, measure the resistance of the PC solenoid valve.

Is the resistance within the specified range?

3.5-4.6 ohms @ 20°C (68°F)

4.2-5.5 ohms @ 70°C (158°F)

Go to Step 12

Go to Step 14

10

Using the J 39200 DMM and the J 35616-A connector test adapter kit, measure the resistance from terminals A, B, C, D, of the 7-way and terminals A, B, C and D of the 4-way automatic transmission wiring harness assembly to the transmission case.

Is the resistance more than the specified value?

250 K ohms

System OK

Go to Step 11

11

  1. Disconnect the 7-way and 4-way automatic transmission 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 12

Go to Step 14

12

  1. Inspect for high resistance or a short.
  2. Inspect the automatic transmission wiring harness assembly at all transmission connecting points and all component connectors for the following conditions:
  3. • Insufficient electrical connections
    • Backed out, or damaged terminals
    • A damaged terminal
    • Reduced terminal tension
    • A chafed wire that could short to bare metal or other wiring
    • A broken wire inside the insulation
    • Moisture intrusion
    • Corrosion
  4. If diagnosing for a possible intermittent condition, move or massage the automatic transmission wiring harness assembly while observing the test equipment for a change.

Did you find high resistance or a short?

--

Go to Step 1

Go to Step 13

13

Replace the automatic transmission wiring harness assembly.

Is the replacement complete?

--

Go to Step 1

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14

Replace the faulty transmission component.

Is the replacement complete?

--

Go to Step 1

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