For 1990-2009 cars

## DTC B2560 RKE Message Validation Error 1st Design

### Circuit Description

The Remote Control Door Lock Receiver (RCDLR) monitors serial communications between it and the Body Control Module (BCM) over the Class 2 data bus. Each valid message received by the RCDLR contains a changing unique rolling code.

### Conditions for Setting the DTC

The fault is set after the RCDLR receives 16 consecutive incorrect messages.

### Action Taken When the DTC Sets

Stores a DTC B2560 in the receivers memory.

### Conditions for Clearing the DTC

• | The conditions for the fault are no longer present.

• | The use of a scan tool.

• | A history DTC will clear after 50 consecutive ignition cycles if the condition for the fault are no longer present.

### Diagnostic Aids

The following conditions may cause intermittent transmitter or receiver operation.

• | Inspect that the transmitter battery terminals are clean and are making good contact with the battery.

• | Any condition which results in the interruption of power to the receiver.

• | Out of range battery or ignition voltage. Normal voltage range is 9.0-16.0 V.

• | A loose or damaged gound.

• | A loose or damaged power supply.

### Test Description

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

1. A weak battery may cause the transmitter to malfunction. This test determines if the battery is the cause. After replacement and programming, the transmitter is operated through all positions. A check is made to see if the DTC resets.

2. If the DTC resets the most likely cause is the transmitter.

3. Both transmitters might be out of sync. This test reprograms and synchronizes both transmitters. After reprogramming both transmitters are checked again.

4. If the DTC resets after both transmitters were reprogrammed and synchronized, the most likely cause is the receiver.

#### DTC 2560 RKE Message Validation Error

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Was the Remote Keyless Entry Diagnostic System Check performed? | -- | Go to Step 2 | Go to Diagnostic System Check - Remote Keyless Entry
2 | Does this DTC set with one particular transmitter? | -- | Go to Step 3 | Go to Step 4
3 |

1. Replace the battery in the transmitter that set the DTC.
2. Reprogram the transmitter. Refer to Transmitter Programming and Transmitter Synchronization .
3. Operate the transmitter through all button and switch positions.

Does DTC B2560 reset?

--

Go to Step 5

Go to Diagnostic System Check - Remote Keyless Entry

4 | Does the DTC set with both transmitters? | -- | Go to Step 6 | Go to Diagnostic System Check - Remote Keyless Entry
5 | Replace the transmitter battery. Refer to Transmitter Battery Replacement . Is the replacement complete? | -- | Go to Diagnostic System Check - Remote Keyless Entry | --
6 |

1. Reprogram and synchronize both transmitters. Refer to Transmitter Programming and Transmitter Synchronization .
2. Operate both transmitters through all button and switch positions.

Does DTC B2560 reset with both transmitters?

--

Go to Step 7

Go to Diagnostic System Check - Remote Keyless Entry

7 | Replace the receiver. Refer to Receiver Replacement . Is the replacement complete? | -- | Go to Diagnostic System Check - Remote Keyless Entry | --

## DTC B2560 RKE Message Validation Error 2nd Design

### Circuit Description

The Remote Control Door Lock Receiver (RCDLR) for the 2nd design RKE system is integrated with the Body Control Module (BCM). A different signal from the transmitter is sent to the receiver when any of the four buttons are pressed on the transmitter. Each signal contains a message to execute a command (e.g., LOCK/UNLOCK drivers door). The receiver transforms the commands and transmits the message to the BCM, which will execute the requested command.

### Conditions for Setting the DTC

A message is received with the correct transmitter ID but the accompanying security information cannot be validated. A message validation counter is increased each time the receiver receives consecutive incorrect security information. When the counter reaches 16, a DTC B2560 is set.

### Action Taken When the DTC Sets

• | Stores a DTC B2560 in the receivers memory.

• | The message validation counter is reset.

• | Receiver operation is disabled for a minimum of 20 seconds.

### Conditions for Clearing the DTC

• | The current status of the DTC becomes a history status when a valid message is subsequently received.

• | The use of a scan tool.

### Diagnostic Aids

The following conditions may cause intermittent transmitter or receiver operation.

• | Inspect that the transmitter battery terminals are clean and are making good contact with the battery.

• | Out of range battery or ignition voltage. Normal voltage range is 9.0-16.0 V.

### Test Description

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

1. A weak battery may cause the transmitter to malfunction. This test determines if the battery is the cause. After replacement and programming, the transmitter is operated through all positions. A check is made to see if the DTC resets.

2. If the DTC resets the most likely cause is the transmitter.

3. Both transmitters might be out of sync. This test reprograms and synchronizes both transmitters. After reprogramming both transmitters are checked again.

4. If the DTC resets after both transmitters were reprogrammed and synchronized, the most likely cause is the receiver in the BCM.

#### DTC 2560 RKE Message Validation Error (2nd Design)

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Was the Body Control Module Diagnostic System Check performed? | -- | Go to Step 2 | Go to Diagnostic System Check - Body Control System
2 | Does this DTC set with one particular transmitter? | -- | Go to Step 3 | Go to Step 4
3 |

1. Replace the battery in the transmitter that set the DTC.
2. Reprogram the transmitter. Refer to Transmitter Programming and Transmitter Synchronization .
3. Operate the transmitter through all button and switch positions.

Does DTC B2560 reset?

--

Go to Step 5

Go to Step 8

4 | Does the DTC set with both transmitters? | -- | Go to Step 6 | --
5 | Replace the transmitter battery. Refer to Transmitter Battery Replacement . Is the replacement complete? | -- | Go to Step 8 | --
6 |

1. Reprogram and synchronize both transmitters. Refer to Transmitter Programming and Transmitter Synchronization .
2. Operate both transmitters through all button and switch positions.

Does DTC B2560 reset with both transmitters?

--

Go to Step 7

--

7 | Replace the BCM. Refer to Body Control Module Replacement in Body Control System. Is the replacement complete? | -- | Go to Diagnostic System Check - Body Control System | --
8 | Verify keyless entry operation. Using the transmitter, lock/unlock the doors, release the trunk lid and fuel filler door. Is the system operating properly? | -- | System OK | --