GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 1999 🢒 Bonneville 🢒 Body and Accessories 🢒 Instrument Panel, Gauges, and Console 🢒 Low Engine Coolant Indicator Inoperative

Low Engine Coolant Indicator Inoperative Pontiac with U50/U2F

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 OFF the ignition switch.
  2. Disconnect the engine coolant level switch connector.
  3. Connect a fused jumper switch between the engine coolant level switch connector terminal C (YEL/BLK) and ground.
  4. Turn the ignition switch to RUN.

Does the LOW COOLANT indicator light?

--

Go to Step 3

Go to Step 4

3

Measure the voltage between the engine coolant level switch connector terminal B (PINK) and A (BLK/WHT).

Is the voltage equal to the specified value?

10-15 V

Go to Step 7

Go to Step 8

4

Inspect CKT 68 (YEL/BLK) for an open or a high resistance.

Is the wiring OK?

--

Go to Step 6

Go to Step 5

5

Repair the open or high resistance in CKT 68 (YEL/BLK).

Did you complete the repair?

--

Go to Instrument Cluster System Check

--

6

Replace the instrument cluster.

Did you complete the repair?

--

Go to Instrument Cluster System Check

--

7

Replace the engine coolant level switch.

Did you complete the repair?

--

Go to Instrument Cluster System Check

--

8

Inspect CKT 239 (PINK) for the following conditions:

  1. An open
  2. High Resistance
  3. Short to ground

Is the wiring OK?

--

Go to Step 10

Go to Step 9

9

Repair the open or short to ground in CKT 239 (PNK).

Did you complete the repair?

--

Go to Instrument Cluster System Check

--

10

Inspect CKT 251 (BLK/WHT) for an open or high resistance.

Is the wiring OK?

--

Go to Instrument Cluster System Check

Go to Step 6

11
  1. Inspect the instrument cluster connector C1 for proper terminal contact at terminal D14 (Oldsmobile) or B5 (Pontiac).
  2. Inspect connector C200 for proper terminal contact at terminal L5 (Pontiac).

Are all of the connector terminals OK?

--

Go to Step 6

Go to Step 12

12

Repair the poor terminal contact.

Did you complete the repair?

--

Go to Instrument Cluster System Check

--

Low Engine Coolant Indicator Inoperative Buick with U23

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 OFF the ignition switch.
  2. Disconnect connector C1 of the powertrain control module (PCM).
  3. Connect a fused jumper from PCM connector C1, terminal 75 to ground.
  4. Turn the ignition switch to the RUN position.

Does the engine coolant temperature indicator illuminate?

--

Go to Step 3

Go to Step 4

3

Inspect PCM connector C1 for proper terminal contact at terminal 

Is terminal contact OK?

--

Go to Engine Controls

Go to Step 5

4

Inspect for an open in CKT 35 (DK GRN).

Is the wiring OK?

--

Go to Step 7

Go to Step 6

5

Repair the poor terminal contact.

Did you complete the repair?

--

Go to Instrument Cluster System Check

--

6

Repair the open in CKT 35 (DK GRN).

Did you complete the repair?

--

Go to Instrument Cluster System Check

--

7
  1. Inspect connector C200 for proper terminal contact at terminal C1.
  2. Inspect the connector for proper terminal contact at terminal 13.

Are the connector terminals OK?

--

Go to Step 9

Go to Step 8

8

Repair the poor terminal contact.

Did you complete the repair?

--

Go to Instrument Cluster System Check

--

9

Replace the remote indicator bank.

Did you complete the repair?

--

Go to Instrument Cluster System Check

--