Low Engine Coolant Indicator Always On
|
Low Engine Coolant Indicator Always On
|
Diagnostic Fault Information
|
Circuit
|
Short to Ground
|
Open/High Resistance
|
Short to Voltage
|
Signal Performance
|
Coolant Level Switch Signal
|
Message OFF
|
Message ON
|
Message ON
|
-
|
Low Reference
|
-
|
Message ON
|
-
|
-
|
Circuit/System Description
|
The indicator lamp for low coolant levels is located in and controlled by the instrument cluster (IPC). The level switch for coolant is located in the coolant's expansion tank. The switch remains open when surrounded by coolant. When the engine coolant level switch is closed for greater than 10 seconds, indicating low coolant, the IPC will turn ON the Low Coolant Indicator lamp. The lamp will also illuminate for approximately 3 seconds during the display test at the start of each ignition cycle.
Schematic Reference
Engine Cooling Schematics
Connector End View Reference
Component Connector End Views
Description and Operation
Cooling System Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References
for scan tool information
Circuit/System Verification
|
1.
|
Ignition OFF, verify the radiator surge tank is filled to the correct level, with engine coolant.
|
2.
|
Ignition ON, check the scan tool Coolant Level Switch parameter. The parameter should display OK.
|
4.
|
The low coolant indicator should be OFF with the engine coolant at the correct level.
|
Note
|
Circuit/System Verification must be performed before performing the Circuit/System Testing.
|
1.
|
Ignition OFF, disconnect the harness connector at the B33 coolant level switch.
|
2.
|
Test for less than 5 Ω between the ground circuit terminal 1 and ground.
|
3.
|
If greater than the specified range, test the ground circuit for an open/high resistance.
|
4.
|
Ignition ON, check the scan tool Coolant Level Switch parameter. The parameter should display OK.
|
5.
|
If not the specified value, test the signal circuit terminal 2 for a short to ground. If the circuit tests normal, replace the P16 IPC.
|
6.
|
Install a 3 A fused jumper wire between the signal circuit terminal 2 and the ground circuit terminal 1. Verify the scan tool Coolant Level Switch parameter displays Low, and the low coolant lamp in the IPC is ON.
|
7.
|
If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the P16 IPC.
|
8.
|
If all circuits test normal, test or replace the B33 coolant level switch.
|
Perform the
Diagnostic Repair Verification
after completing the diagnostic procedure.