Pinpoint Test D: DTC B1602 - Pats Received Invalid Format Of Key-Code From Ignition Key Transponder

WARNING: This page is about a different car, the 2008 Mercury Mariner and 2008 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Large metallic objects, electronic devices on the key ring that can be used to purchase gasoline or similar items, or a second key on the same key ring as the PATS key may cause a vehicle starting concern and record DTCs under certain conditions. If a fault cannot be identified, examine the customer key ring for such objects or devices. If present, inform the customer that they need to keep these objects from touching the PATS key while starting the engine. These objects and devices cannot damage the PATS key, but can cause a momentary concern if they are too close to the key during engine start. If a concern occurs, turn the ignition off and restart the engine with all other objects on the key ring held away from the ignition key. Check to make sure the PATS key used by the customer is an approved Ford PATS key (PATS keys from Ford, Rotunda, Strattec, and HUF are approved Ford PATS keys).

D1 RETRIEVE THE DTCs
- If only one key is available, cut a new key and program the keys. Refer to Integrated Keyhead Transmitter (IKT) Key Programming Using Diagnostic Equipment .
- Key in OFF position.
- Connect the diagnostic tool.
- Key in ON position.
- Enter the following diagnostic mode on the diagnostic tool: Clear the DTCs
- Key in OFF position.
- Key in ON position.
- Enter the following diagnostic mode on the diagnostic tool: Retrieve the DTCs
- Is DTC B1602 retrieved for one or both PATS keys?
1. YES : If DTC B1602 is retrieved for one key, REPLACE that key and PROGRAM the new key. REFER to Integrated Keyhead Transmitter (IKT) Key Programming Using Diagnostic Equipment . CLEAR the DTCs. CYCLE the ignition. REPEAT the self-test.
  If DTC B1602 is retrieved for both PATS keys, go to D2 .
2. NO : The system is OK. CHECK all the customer PATS keys by attempting to start the vehicle with each key to VERIFY all other PATS keys are programmed.
D2 INSTALL A NEW PATS TRANSCEIVER
NOTE: Replacement of the PATS transceiver does not require the PATS keys to be programmed into the IC again.
- Key in OFF position.
- Install a new PATS transceiver. Refer to Passive Anti-Theft System (PATS) Transceiver .
- Key in ON position.
- Enter the following diagnostic mode on the diagnostic tool: Clear the DTCs
- Key in OFF position.
- Key in ON position.
- Enter the following diagnostic mode on the diagnostic tool: Retrieve the DTCs
- Are any PATS DTCs retrieved?
1. YES : Go to D3.
2. NO : The system is OK. CHECK all the customer PATS keys by attempting to start the vehicle with each key to VERIFY all other PATS keys are programmed.
D3 CHECK FOR CORRECT IC OPERATION
NOTE: When a new IC is installed, the PATS keys must be programmed into the new IC.

NOTE: When a new IC is installed, the parameters must be reset in the IC and the PCM.
- Disconnect all the IC connectors.
- Check for:
  - corrosion
  - damaged pins
  - pushed-out pins
- Connect all the IC connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
1. YES : INSTALL a new IC. REFER to INSTRUMENT CLUSTER (IC), MESSAGE CENTER, AND WARNING CHIMES article. RESET the parameters in both the IC and the PCM. REFER to Passive Anti-Theft System (PATS) Parameter Reset . PROGRAM the PATS keys into the new IC. REFER to Integrated Keyhead Transmitter (IKT) Key Programming Using Diagnostic Equipment . CYCLE the ignition. REPEAT the self-test.
2. NO : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. CYCLE the ignition. REPEAT the self-test.