For 1990-2009 cars

## DTC B0936 L61

### Circuit Description

When engine coolant is at the proper level, the low coolant switch is closed. When in this condition, battery voltage is applied to the low coolant 1478 input of the body control module (BCM).

When coolant is below the proper level, the coolant switch opens. Because no voltage is applied to circuit 1478, the BCM responds by sending a serial data message to the instrument panel cluster to turn ON the LOW COOLANT telltale.

The BCM has an internal timer, which will not turn ON the low coolant telltale unless the coolant level is low for greater than 30 seconds. The timer avoids coolant sloshing, falsely turning ON the LOW COOLANT telltale.

### Conditions for Setting the DTC

• | The ignition is in the RUN position.

• | Low coolant condition -- No voltage on circuit 1478 for greater than 30 seconds.

### Diagnostic Aids

• | Check for a poor connection at the BCM. Inspect the harness connector for backed out terminals, improper terminal mating, broken connector locks, improperly formed or damaged terminals, and poor terminal to wire connection (terminal crimped over wire insulation and not conductors).

• | Inspect the wiring harness for damage. Check for broken or chafed insulation.

• | Check for a poor connection at the low coolant switch.

• | If a fault is suspected to be intermittent, wiggling the harness wiring may help in locating the fault.

## DTC B0936 L81

### Circuit Description

When the engine coolant is at the proper level, the low coolant switch is closed. When in this condition, the battery voltage is applied to the low coolant 1478 input of the body control module (BCM).

When coolant is below the proper level, the coolant switch opens. Because no voltage is applied to the circuit 1478, the BCM responds by sending a serial data message to the instrument panel cluster to turn On the "LOW COOLANT" telltale.

The BCM has an internal time, which will not turn On the low coolant telltale unless the coolant level is low for greater than 30 seconds. The timer avoids coolant "sloshing" falsely turning On the "LOW COOLANT" telltale.

### Conditions for Setting the DTC

• | Ignition in RUN Position.

• | Low coolant condition (No voltage on circuit 1478 for greater than 30 seconds)

### Diagnostic Aids

• | Check for poor connection at the BCM. Inspect the harness connector for bracket out terminals, improper terminal mating, broken connector locks, improperly formed or damaged terminals and poor terminal to wire connection (terminal crimped over wire insulation and not conductors).

• | Inspect the wiring harness for damage. Check for broken or chafed insulation.

| Check for poor connection at the low coolant switch.

• | If fault is suspected to be intermittent, wiggling the harness wiring may help in locating fault.

### DTC B0936