For 1990-2009 cars

### DTC Descriptor

DTC P2536: Ignition Accessory Switch Circuit

### Circuit Description

The engine control module (ECM) monitors the accessory voltage circuit and compares the voltage status with the information received from the body control module (BCM) via CAN serial data. If the ECM detects that the CAN voltage status information does not match the actual voltage feedback on the accessory voltage circuit, the DTC will be set.

### Conditions for Running the DTC

Ignition switch is ACC.

### Conditions for Setting the DTC

The ECM detects power mode master accessory terminal status does not match the ignition switch position.

### Action Taken When the DTC Sets

DTC P2536 is type C DTC. Refer to Powertrain Diagnostic Trouble Code (DTC) Type Definitions.

### Conditions for Clearing the MIL/DTC

DTC P2536 is type C DTC. Refer to Powertrain Diagnostic Trouble Code (DTC) Type Definitions.

Step | Action | Value | Yes | No
--- | --- | --- | --- | ---
1 | Did you perform the Diagnostic System Check? | -- | Go to Step 2 | Go to Diagnostic System Check - Vehicle
2 | Observe the DTC information stored in the ECM with a scan tool. Are the DTCs that begin with "U" also set? | -- | Go to applicable DTC table | Go to Step 3
3 | Are the DTCs related to system voltage also set? | -- | Go to applicable DTC table | Go to Step 4
4 | Observe the DTC information stored in the BCM with a scan tool. Are there any DTCs stored? | -- | Go to applicable DTC table | Go to Step 5
5 | Inspect the accessory voltage circuit between the wiring harness connector J1 terminal 73 of the ECM and the connector J1 terminal 19 of the BCM for the following conditions:

• | A short to voltage

• | A short to ground

• | An open/high resistance

Did you find and correct the condition?

--

Go to Step 7

Go to Step 6

6 | Replace the ECM. Refer to Control Module References. Did you complete the replacement? | -- | Go to Step 7 | --
7 |

1. Clear the DTCs with a scan tool.
2. Turn OFF the ignition for 30 seconds.
3. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.

Did the DTC fail this ignition?

--

Go to Step 2

Go to Step 8

8 | Check if any additional DTCs are set. Are there any DTCs that have not been diagnosed? | -- | Go to applicable DTC table | System OK