For 1990-2009 cars
Body Control Module Components
Cell 51: SDM, Washer Solvent Lever Sensor, Seat Belt Switch and Park Brake Switch

### Circuit Description

This is a trouble code (both current and history) that indicates the parklamps were not ON when the ALC relay output was ON.

### Conditions for Setting the DTC

Meet all of the following conditions:

• | The ALC option is enabled and ignition one is active.

• | The ALC parklamp output is active.

• | The parklamps active discrete input is not active for five seconds.

### Action Taken When the DTC Sets

• | Stores the DTC B2585 in the body control module (BCM) memory.

• | The SERVICE VEHICLE SOON indicator will illuminate.

### Conditions for Clearing the DTC

• | The BCM reads the proper parklamp voltage.

• | Conditions for the fault are no longer present.

• | All the BCM history codes will be cleared after 100 ignition cycles (from OFF to RUN) with no current codes active during the 100 ignition cycles.

• | Use the scan tool.

### Diagnostic Aids

• | If B+ is found on the BCM parklamp relay output, check the ALC parklamp relay control output and the power to the relay or check the turn/headlamp/wiper switch for possible problems.

• | If the DTC is a history DTC, the problem may be intermittent. Try performing the above tests while wiggling the wiring and connectors. This can often cause the malfunction to appear.

Step | Action | Yes | No
--- | --- | --- | ---
Important: A short to ground will cause an open fuse(s). Before performing this diagnostic procedure, inspect the fuse(s) for an open.
1 | Was the body control module (BCM) System Check performed? | Go to Step 2 | Go to the Body Control Module System Check
2 | Are there any other ALC DTCs showing? | Go to the other ALC DTC table first | Go to Step 3
3 |

1. Place the headlamp switch in the PARK position.
2. Use a scan tool to read the BCM INPUT for the PARK LAMP INPUT.

Does the PARK LAMP INPUT indicate Applied?

Go to Intermittents and Poor Connections Diagnosis in Wiring Systems

Go to Step 4

4 | Are the park lamps illuminated? | Go to Step 7 | Go to Step 5
5 |

1. Disconnect the Automatic Lamp Control Park Lamp Relay.
2. Probe the switch side battery positive voltage circuit of the Automatic Lamp Control Park Lamp Relay with a test lamp that is connected to a good ground.

Does the test lamp illuminate?

Go to Step 6

Go to Step 10

6 |

1. Install a 15- amp fused jumper wire between the switch side battery positive voltage circuit of the Automatic Lamp Control Park Lamp Relay and the park lamp voltage supply circuit of the Automatic Lamp Control Park Lamp Relay.
2. Use a scan tool to read the BCM INPUT for the PARK LAMP INPUT.

Does the PARK LAMP INPUT indicate Applied?

Go to Step 8

Go to Step 7

7 | Test for an open, high resistance, or short to ground in the park lamp voltage supply circuit. Refer to following:

• | Testing for Continuity in Wiring Systems

• | Testing for Short to Ground in Wiring Systems

• | Wiring Repairs in Wiring Systems

Did you find and correct the condition?

Go to Step 13

Go to Step 9

8 | Inspect for poor connections at the Automatic Lamp Control Park Lamp Relay. Refer to Intermittents and Poor Connections Diagnosis and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 13 | Go to Step 11
9 | Inspect for poor connections at the harness connector of the BCM. Refer to Intermittents and Poor Connections Diagnosis and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 13 | Go to Step 12
10 | Repair an open, high resistance, or short to ground in the switch side battery positive voltage circuit of the Automatic Lamp Control Park Lamp Relay. Refer to the following:

• | Testing for Continuity in Wiring Systems

• | Testing for Short to Ground in Wiring Systems

• | Wiring Repairs in Wiring Systems

Did you complete the repair?

Go to Step 13

--

11 | Replace the Automatic Lamp Control Park Lamp Relay. Did you complete the replacement? | Go to Step 13 | --
12 | Replace the BCM. Refer to Body Control Module Replacement . Is the repair complete? | Go to Step 13 | --
13 | Clear the DTCs from the memory. Are the DTCs cleared from the memory? | Go to the Body Control Module System Check | --