B1A25 Invalid key

Set condition DTC B1A25 Invalid key

When the Sentry Key Remote Entry Module (SKREEM) also known as the WCM does not receive a transponder response after 8 consecutive transponder read attempt within 2.0 seconds. When the key that is being used is programmed for a different vehicle.

Posible causes DTC B1A25 Invalid key

• Key that has been previously programmed for another vehicle.
• Multiple key operation.
• Ignition key.
• Wireless Control Module (WCM)/Sentri Key Remote Entry Module (SKREEM).
• Intermittent wiring harness problem.

Step by step diagnose DTC B1A25 Invalid key

Step 1. Determining if DTC is current

Note: An external Radio-frequency Identification (RFID) key (and/or pass/radio key), such as one used to again access to a 24 hour gym, can cause this DTC to set and create a no start condition. Inspect the customers key chain for any type of RFID key. If one is not found, question the customer to see if a spare key chain has this RFID key on it or if it was removed from the oroginal key chain before the vehicle was released for service. If a RFID key is present, remove the ignition key from the vehicle and remove the RFID key from the key chain. For GPEC equipped vehicle, disconnect the battery and wait a minimum of 5 minutes, reconnect and attempt to start the vehicle. For NGC equipped vehicles, turn the ignition on a minimum for one hour, and then attempt to start the vehicle. If the vehicle does not start, continue with the diagnostic test.

Note: Verify the key being used is the proper key for this vehicle and blank key. If the key being programmed is not blank (one that has been programmed for another vehicle) this fault will set.

With the scan tool, read and erase the WCM DTC.

Note: Perform the following test several times to make sure the DTC is current.

Turn the ignition off, wait 10 seconds, turn the ignition on. With the scan tool, read WCM DTC.

Does the scan tool display tha DTC that was previously erased?

YES, go to step 2.

NO, go to step 6.

Step 2. Checking for multiple keys

Are there multiple vehicle ignition keys available?

YES, go to step 3.

NO, go to step 4.

Step 3. Multiple key operation

Note: Perform the following steps using one of the vehicle ignition keys. When finished, repeat the procedure using each of the other vehicle keys, one at a time.

With the scan tool erase DTC, turn the ignition off, wait 10 seconds. Turn the ignition on, read the WCM DTC on the scan tool.

Is the DTC present for all ignition keys?

YES, replace and program the WCM. Perform the WCM verifcation test.

NO, replace the ignition keys that cause the SKIM DTC.

Step 4. Reprogram key

With the scan tool, attempt to program the ignition key to the WCM. With the scan tool, erase the WCM DTC. Wait 10 seconds, turn the ignition on, read the WCM DTC.

Does the DTC set again?

YES, go to step 5.

NO, test complete.

Step 5. Program new ignition key

Replace the ignition key with a new key. With the scan tool, program the new ignition key to the WCM and erasethe WCM DTC. Turn the ignition off, wait 10 seconds, turn the ignition on, read the WCM DTC.

Does the DTC set again?

YES, replace and program the Sentry Key Remote Entry Module (SKREEM). Perform the WCM Verification test.

NO, test complete.

Step 6. Intermittent wiring harness problem

Turn the ignition off.

Note: Check the following items:

• Visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or partially broken wires.
• Visually inspect the related wiring harness connectors. Look for broken, bent, pushed out, or corroded terminals.
• Perform any technical service bulletins that may apply.

Were any problems found?

YES, repair wiring harness/connectors as necessary.

NO, test complete.

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