For 1990-2009 cars

## Engine Coolant Temperature Indicator Inoperative Pontiac

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Did you perform the Instrument Cluster System Check? | -- | Go to Step 2 | Go to Instrument Cluster System Check
2 |

1. Turn the ignition switch off.
2. Disconnect the engine coolant temperature (ECT) sensor connector.
3. Connect 1 red clip lead of J33431 I/P tester to the engine coolant temperature (ECT) sensor connector terminal C.

Connect 1 red clip lead to ground.

4. Turn the ignition switch to run.
5. Adjust the J33431 resistance dials to 1400 ohms, 93 ohms and then to 55 ohms.

Does the coolant temperature gauge indicate minimum, midscale and maximum temperature?

--

Go to Step 7

Go to Step 3

3 | Inspect CKT 36 (LT GRN) for an open or a short to ground. Was a problem found with CKT 36? | -- | Go to Step 8 | Go to Step 4
4 | Inspect connector C200 for proper terminal contact at terminal A8. Was a poor connection found? | -- | Go to Step 9 | Go to Step 5
5 | Inspect connector C101 for proper terminal contact at terminal B3. Was a poor connection found? |  | Go to Step 10 | Go to Step 6
6 | Inspect the instrument cluster connector for proper terminal contact at terminal B11. Was a poor connection found? |  | Go to Step 11 | Go to Step 12
7 | Was a poor connection found? |  | Go to Step 13 | Go to Step 14
8 | Repair CKT 36 (LT GRN) for an open or a short to ground. Refer to Repairing Damaged Wire Insulation in Wiring Systems. Is the repair complete? | -- | Go to Instrument Cluster System Check | --
9 | Repair connector C200 terminal cavity A8. Refer to Terminal Repair in Wiring Systems. Is the repair complete? | -- | Go to Instrument Cluster System Check | --
10 | Repair connector C101 terminal cavity B3. Refer to Terminal Repair in Wiring Systems. Is the repair complete? | -- | Go to Instrument Cluster System Check | --
11 | Repair the instrument cluster terminal cavity B11. Refer to Terminal Repairs in Wiring Systems. Is the repair complete? | -- | Go to Instrument Cluster System Check | --
12 | Replace the instrument cluster. Refer to Instrument Cluster Replacement in Instrument Panel, Gauges, and Console. Is the replacement complete? | -- | Go to Instrument Cluster System Check | --
13 | Repair the engine coolant temperature (ECT) sensor connector terminal. Refer to Terminal Repair in Wiring Systems. Is the repair complete? | -- | Go to Instrument Cluster System Check | --
14 | Replace the engine coolant temperature sensor. Refer to Engine Coolant Temperature Sensor Replacement in Engine Controls. Is the replacement complete? | -- | Go to Instrument Cluster System Check | --

## Engine Coolant Temperature Indicator Inoperative Buick

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Did you perform the Instrument Cluster System Check? | -- | Go to Step 2 | Go to Instrument Cluster System Check
2 |

1. Turn the ignition switch OFF.
2. Disconnect the engine coolant temperature ECT sensor connector.
3. Connect 1 red clip lead of the J 33431-C to the engine coolant temperature ECT sensor connector terminal C.

Connect 1 red clip lead of the J 33431-C to ground.

4. Turn the ignition switch to RUN.
5. Adjust the J 33431-C resistance dials to 1400 ohms, 93 ohms and then to 55 ohms.

Does the coolant temperature gauge indicate minimum, midscale and maximum temperature?

--

Go to Step 7

Go to Step 3

3 | Inspect one of the following circuits for an open or a short to ground:

1. For U50/U2F, CKT 135 (DK GRN), and CKT 36 (LT GRN)
2. For UB3 CKT 36

Was a problem found?

--

Go to Step 9

Go to Step 4

4 | Inspect connector C101 cavity B3 for proper terminal contact. Was a poor connection found? | -- | Go to Step 10 | Go to Step 5
5 | Inspect connector C200 cavity A8 for proper terminal contact. Was a poor connection found? | -- | Go to Step 11 | Go to Step 6
6 | Inspect one of the following instrument cluster terminals for proper terminal contact:

1. For UB3, instrument cluster connector terminal cavity A9
2. For U50/U2F instrument cluster connector terminal cavity A11

Was a poor connection found?

--

Go to Step 12

Go to Step 13

7 | Inspect the ECT sensor connector for proper terminal contact. Was a poor connection found? | -- | Go to Step 14 | Go to Step 8
8 | Test for an open or high resistance at the ECT ground. Does the resistance measure near the specified value? | ∞ | Go to Step 14 | --
9 | Repair one of the following circuits for an open or a short to ground:

• | For U50/U2F, CKT 135 (DK GRN) or CKT 36 (LT GRN)

• | For UB3, CKT 36 (LT GRN)

Refer to Repairing Damaged Wire Insulation in Wiring Systems.

Is the repair complete?

--

Go to Instrument Cluster System Check

--

10 | Repair connector C101 cavity B3 terminal. Refer to Terminal Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Instrument Cluster System Check | --
11 | Repair connector C200 cavity A8 terminal. Refer to Terminal Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Instrument Cluster System Check | --
12 | Repair the instrument cluster connector terminal cavity A9 (UB3 only) or cavity A11 (U50/U2F only). Refer to Terminal Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Instrument Cluster System Check | --
13 | Replace the instrument cluster. Refer to IP Cluster Replacement in Instrument Panel, Gauges, and Console. Is the replacement complete? | -- | Go to Instrument Cluster System Check | --
14 | Replace the engine coolant temperature sensor. Refer to Engine Coolant Temperature Sensor Replacement in Engine Controls. Is the replacement complete? | -- | Go to Instrument Cluster System Check | --