GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2003 🢒 DeVille 🢒 Suspension 🢒 Automatic Level Control 🢒 DTC C0625

Circuit Description

The automatic level control sensor is a potentiometer. The RIM determines the height of the rear of the vehicle based on the voltage from the automatic level control sensor. The RIM raises or lowers the rear of the vehicle in order to keep the vehicle level.

Conditions for Running the DTC

The RIM is powered up and DTC B1327 is not set.

Conditions for Setting the DTC
    • The automatic level control signal voltage is less that 0.35 V or greater than 4.75 V.
    • The above conditions are present for greater than 10 seconds.

Action Taken When the DTC Sets

The automatic level control suspension will be inoperative.

Conditions for Clearing the MIL/DTC

The RIM does not detect a voltage above or below the predetermined value during the diagnostic self test.

Diagnostic Aids

Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. Tests for the proper operation of the circuit in the high range. If the fuse in the jumper opens when you perform the test, the signal circuit is shorted to ground.

    2.

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

Step

Action

Value(s)

Yes

No

Schematic Reference: Automatic Level Control Schematics

1

Did you perform the Automatic Level Control Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - Automatic Level Control

2
  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. Observe the Suspension Sensor data parameter in the Body Control Module data list using the scan tool.

Does the scan tool indicate the voltage is within the specified range?

0.35-4.75  V

Go to Diagnostic Aids

Go to Step 3

3
  1. Turn OFF the ignition.
  2. Disconnect the suspension position sensor.
  3. Turn ON the ignition leaving the engine OFF.
  4. Measure the voltage from the suspension position sensor 5 volt reference circuit to a good ground.

Does the voltage measure near the specified value?

5 V

Go to Step 4

Go to Step 7

4

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

Does the scan tool indicate that the suspension position sensor voltage is greater than the specified value?

4.75 V

Go to Step 5

Go to Step 8

5

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

Does the voltage measure less than the specified value?

4.75 V

Go to Step 6

Go to Step 9

6
  1. Turn OFF the ignition.
  2. Disconnect the negative battery cable.
  3. Measure the resistance from the ground circuit of the suspension position sensor to a good ground.

Does the resistance measure less than the specified value?

5 ohms

Go to Step 11

Go to Step 10

7

Test the 5-volt reference circuit of the suspension 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 15

Go to Step 12

8

Test the 5-volt signal circuit of the suspension 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 15

Go to Step 12

9

Test the signal circuit of the suspension 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 15

Go to Step 12

10
  1. Disconnect the RIM.
  2. Test the ground circuit of the suspension position sensor for a 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 15

Go to Step 12

11

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 15

Go to Step 13

12

Inspect for poor connections at the harness connector of the RIM. 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 15

Go to Step 14

13

Replace the suspension position sensor. Refer to Automatic Level Control Sensor Replacement .

Did you complete the replacement?

--

Go to Step 15

--

14

Replace the RIM. Refer to Rear Integration Body Control Module Replacement in Body Control System.

Did you complete the replacement?

--

Go to Step 15

--

15
  1. Clear the DTCs using the scan tool.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

--

Go to Step 2

System OK