Hill Descent Control Indicator Malfunction
Diagnostic Instructions
Diagnostic Fault Information
Circuit
| Short to Ground
| Open/High Resistance
| Short to Voltage
| Signal Performance
|
Signal
| --
| 1
| --
| --
|
Ground
| --
| 1
| --
| --
|
1. Hill Descent Control Switch Malfunction
|
Circuit/System Description
The hill descent control system switch is a normally open switch that closes when the switch is activated. When activated, the switch grounds the hill descent control system signal circuit. The body control module (BCM) converts the signal into serial data, which is used by the electronic brake control module (EBCM) to enable/disable the hill descent control system.
Reference Information
Schematic Reference
Antilock Brake System Schematics
Connector End View Reference
Component Connector End Views
Description and Operation
ABS Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the S48A Multi-Function Switch Instrument Panel or S48D Multi-Function Switch 2 Instrument Panel.
- Ignition OFF, test for less than 5 Ω between the ground circuit terminal listed below and ground.
• | Terminal 2 (C140/Long Body) |
• | Terminal 16 (C105/Short Body) |
⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
- Ignition ON, verify the scan tool Hill Descent Switch parameter is Inactive.
⇒ | If not the specified value, test the appropriate signal circuit for a short to ground. |
- Install a 3 A fused jumper wire between the appropriate signal circuit terminal and the ground circuit terminal listed below. Verify the scan tool Hill Descent Switch parameter is Active.
• | Signal Terminal 1 and Ground Terminal 2 (C140/Long Body) |
• | Signal Terminal 4 and Ground Terminal 16 (C105/Short Body) |
⇒ | If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the DTC resets, replace the BCM. |
- If all circuits test normal, test or replace the S48A Multi-Function Switch Instrument Panel or S48D Multi-Function Switch 2 Instrument Panel.
Component Testing
- Ignition OFF, disconnect the harness connector at the S48A Multi-Function Switch Instrument Panel or S48D Multi-Function Switch 2 Instrument Panel.
- Test for infinite resistance between the appropriate signal terminal and the ground terminal listed below with the switch in the open position.
• | Signal Terminal 1 and Ground Terminal 2 (C140/Long Body) |
• | Signal Terminal 4 and Ground Terminal 16 (C105/Short Body) |
⇒ | If not the specified value, replace the S48A Multi-Function Switch Instrument Panel or S48D Multi-Function Switch 2 Instrument Panel. |
- Test for less than 3 Ω between the appropriate signal terminal and the ground terminal listed below with the switch in the closed position.
• | Signal Terminal 1 and Ground Terminal 2 (C140/Long Body) |
• | Signal Terminal 4 and Ground Terminal 16 (C105/Short Body) |
⇒ | If greater than the specified range, replace the S48A Multi-Function Switch Instrument Panel or S48D Multi-Function Switch 2 Instrument Panel. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
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