GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2001 🢒 Yukon XL - 4WD 🢒 Suspension 🢒 Real Time Damping (RTD) 🢒 DTC C0615, C0620, C0625, or C0630

Circuit Description

The position sensor provides an analog signal voltage between 0.5 and 4.5 volts to the suspension control module. This signal voltage represents the wheel's position relative to the body. The suspension control module provides a reference and a low reference to the sensor.

Conditions for Running the DTC

Under normal driving conditions.

Vehicle speed greater than 0 km/h (0 mph.

Conditions for Setting the DTC

The suspension control module senses a position signal voltage below 0.5 volts or above 4.5 volts.

Action Taken When the DTC Sets
    • All four dampers will be commanded to their OFF state.
    • The SERVICE RIDE CONTROL message will be displayed.
    • Stores a DTC C0615, C0620, C0625 or C0630 in the suspension control module memory.

Conditions for Clearing the DTC
    • The suspension control module no longer senses a position signal voltage out of range with vehicle speed greater than 0 km/h (0 mph).
    • Using a scan tool.
    • A history DTC will clear after 100 consecutive ignition cycles if the condition for the malfunction is no longer present.

Diagnostic Aids

       Important: Before proceeding with the diagnosis do a visual inspection of the mechanical aspects of the sensor and its components. Ensure the sensor and the sensor link is not bent, disconnected, or insulation on wires are not rubbed through or damaged in any way.

If DTC C0870 is present, repair the malfunction for this DTC before diagnosing DTC C0615, C0620, C0625 or C0630.

    • A faulty sensor voltage reading may result if the vehicle is or has been on a host that allows the suspension to hang free.
    • The following conditions may cause the malfunction to occur:
       - A short to voltage on the 5 volt reference circuit
       - A short to ground on the 5 volt reference circuit
       - An open in the 5 volt reference circuit to the position sensor
       - A short to voltage on the position sensor signal circuit
       - A short to ground on the position sensor signal circuit
       - An open in the position sensor signal circuit
       - An open in the position sensor low reference circuit
       - A malfunctioning position sensor
       - A disconnected, bent or damaged sensor link

Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

  1. Check the supension position sensor data parameter.

  2. Tests for the proper operation of the circuit in the low voltage range.

    3.

  3. Tests for a short to voltage in the 5 volt reference circuit.

    4.

  4. Tests for the proper operation of the circuit in the low voltage range. If the fuse in the jumper opens when you perform this test, the signal circuit is shorted to voltage.

  5. Tests for a high resistance or an open in the ground circuit.

Step

Action

Value(s)

Yes

No

Schematic Reference: Suspension Controls Schematics

1

Important: If DTC C0870 is present, perform the diagnosis for DTC C0870 first.

Did you perform the RTD Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - Real Time Damping

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, observe the position sensor data parameter in the suspension control module data list.

Does the scan tool indicate that the position sensor data parameter is within the specified range?

0.5-4.5 V

Go to Diagnostic Aids

Go to Step 3

3

  1. Turn OFF the ignition.
  2. Disconnect the suspension position sensor connector.
  3. Turn ON the ignition, with the engine OFF.
  4. With a scan tool, observe the suspension position sensor data parameter.

Does the scan tool indicate that the position sensor data parameter is less than the specified value?

0.5 V

Go to Step 4

Go to Step 8

4

Measure the voltage between the 5 volt reference circuit of the position sensor and a good ground.

Does the voltage measure near the specified value?

5 V

Go to Step 5

Go to Step 6

5

  1. Turn OFF the ignition.
  2. Connect a 3 amp fused jumper wire between the 5 volt reference circuit of the position sensor and the signal circuit of the position sensor.
  3. Turn ON the ignition, with the engine OFF.
  4. With a scan tool, observe the position sensor data parameter.

Does the scan tool indicate that the position sensor data parameter is greater than the specified value?

4.5 V

Go to Step 7

Go to Step 9

6

Does the voltage measure greater than the specified value?

5.5 V

Go to Step 10

Go to Step 11

7

  1. Disconnect the fused jumper wire.
  2. Measure the voltage between the 5 volt reference circuit of the position sensor and the low reference circuit of the position sensor.

Does the voltage measure less than the specified value?

3.5 V

Go to Step 12

Go to Step 13

8

Test the signal circuit of the position sensor for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 17

Go to Step 14

9

Test the signal circuit of the position sensor for a short to ground, high resistance, or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 17

Go to Step 14

10

Test the 5 volt reference circuit of the position sensor for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 17

Go to Step 14

11

Test the 5 volt reference circuit of the position sensor for a short to ground, high resistance, or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 17

Go to Step 14

12

Test the low reference circuit of the suspension position sensor for high resistance or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 17

Go to Step 14

13

Inspect for poor connections at the harness connector of the suspension position sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 17

Go to Step 15

14

Inspect for poor connections at the harness connector of the suspension control module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 17

Go to Step 16

15

Replace the suspension position sensor. Refer to Electronic Suspension Front Position Sensor Replacement , Electronic Suspension Rear Position Sensor Replacement - Left Side or Electronic Suspension Rear Position Sensor Replacement - Right Side .

Did you complete the replacement?

--

Go to Step 17

--

16

Important: When replacing the suspension control module the replacement module must be calibrated.

Replace the suspension control module. Refer to Electronic Suspension Control Module Replacement .

Did you complete the replacement?

--

Go to Step 17

--

17
  1. Reconnect any previously disconnected components.
  2. Use the scan tool in order to clear the DTCs.
  3. Operate the vehicle (road test) within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

--

Go to Step 2

System OK