Bonneville V6-3800 3.8L Supercharged (1992)
Temperature Gauge: Component Tests and General Diagnostics
Test E: Coolant Temperature Gage Short Test
Disconnect the Coolant Temperature Sender terminal and turn the Ignition Switch to RUN.
^ If the Coolant Temperature Gage indicates C, replace the Coolant Temperature Sender.
^ If the Coolant Temperature Gage does not indicate C, check the DK GRN/WHT (635) and WHT/BLK (235) wires for a short to ground. If all wires
are good, replace the Instrument Cluster.
Test F: Coolant Temperature Gage Open Test
Disconnect the Coolant Temperature Sender terminal. jumper the DK GRN/WHT (635) wire to ground and turn the Ignition Switch to RUN.
^ If the Coolant Temperature Gage indicates H, replace the Coolant Temperature Sender.
^ If the Coolant Temperature Gage still indicates C, check the DK GRN/WHT (635) and WHT/BLK (235) wires, and Gage connections for an open. If
OK, replace the Instrument Cluster.
Test G: Coolant Temperature Gage Accuracy Test
Disconnect the Coolant Temperature Sender terminal. Connect one red clip lead of the J-33431 tester to the harness terminal DK GRN/WHT (635)
wire, and the other red clip lead to ground. Adjust the resistance dials of the tester to 1400 ohms, 93 ohms and then to 55 ohms. The Coolant
Temperature Gage should indicate C, midscale, and then H.
^ If the Gage indicates correctly, the wiring and Gage are good. Replace the Coolant Temperature Sender.
^ If the Gage does not indicate correctly, check the Gage connections and DK GRN/WHT (635) and WHT/BLK (235) wires. If they are OK, replace
the Instrument Cluster.
Test F: Coolant Temperature Gage Short Test
Disconnect the Coolant Sensor connector and turn the Ignition Switch to RUN.
^ If the Coolant Temperature Gage indicates maximum, then minimum and remains at minimum, replace the Coolant Sensor.
^ If the Coolant Temperature Gage does not indicate maximum, then minimum and remain at minimum, check the YEL (510) wires for a short to
ground. If all wires are good, replace the Instrument Cluster.
Test G: Coolant Temperature Gage Open Test
Disconnect the Coolant Sensor connector. Jumper the YEL (510) wire to ground and turn the Ignition Switch to RUN.
^ If the Coolant Temperature Gage indicates maximum, then minimum and remains at minimum, replace the Coolant Sensor.
^ If the Coolant Temperature Gage still indicates minimum, check the YEL (510) wire for an open. If OK, replace the Instrument Cluster.
Test H: Coolant Temperature Gage Accuracy Test
Disconnect the Coolant Sensor connector. Connect one red clip lead of the GM J-33431 tester to the harness terminal YEL (510) wire, and the other
red clip lead to ground. Adjust the resistance dials of the tester to 1400 ohms, 93 ohms and then to 40 ohms. The Coolant Temperature Gage should
indicate minimum, midscale, and then maximum.
^ If the Gage indicates correctly, the wiring and Gage are good. Replace the Coolant Sensor.
^ If the Gage does not indicate correctly, check the YEL (510) wire. If OK, replace the Instrument Cluster.
Component Diagnostic Tests - Indicator Cluster
Disconnect the Coolant Temperature Sender terminal. Connect one red clip lead of the J-33431 tester to the harness terminal DK GRN/WHT (835)
wire, and the other red clip lead to ground. Adjust the resistance dials of the tester to 1365 ohms, and then to 55 ohms. The Coolant Temperature Gage
should indicate C, then move toward H as the resistance is decreased.
^ If the Gage indicates correctly, the wiring and Gage are good. Replace the Coolant Temperature Sender.
^ If the Gage does not indicate correctly, check the DK GRN/WHT (835) wires and WHT/BLK (235) wires for high resistance. If they are OK, replace
the Instrument Cluster.
