Pinpoint Test B: DTC B1600 - PATS Ignition Key Transponder Signal Is Not Received

WARNING: This page is about a different car, the 2010 Lincoln Town Car. However, it is still accessible from the selected car via links, so may be relevant.

Normal Operation

During each vehicle start sequence, the passive anti-theft system (PATS) transceiver reads the PATS key identification code and sends the data to the PCM.

DTC B1600 (PATS Ignition Key Transponder Signal Is Not Received) - sets when no PATS key has been read by the PCM.

This pinpoint test is intended to diagnose the following:

PATS key
PATS transceiver
PCM

PINPOINT TEST B: DTC B1600 - PATS IGNITION KEY TRANSPONDER SIGNAL IS NOT RECEIVED

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 vehicle starting concerns 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 key 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, or HUF are approved Ford PATS keys.)

B1 RETRIEVE THE DTCs
- Key in OFF position.
- Connect the diagnostic tool.
- Key in ON position.
- Clear the PCM DTCs.
- Key in OFF position.
- Key in ON position.
- Retrieve the PCM DTCs.
- Is DTC B1600 retrieved?
1. YES : Go to B2.
2. NO : If DTCs other than PATS PCM DTCs are retrieved, REFER to the Introduction - Gasoline Engines article.
  If no PATS DTCs are retrieved, the system is OK. The concern may have been caused by interference from another object.
B2 CHECK BOTH PATS KEYS
NOTE: Check to make sure the new PATS keys are approved Ford encoded PATS keys. Unapproved PATS keys do not always operate correctly over various temperature ranges. (PATS keys from Ford, Rotunda, Strattec, or HUF are approved Ford PATS keys.)
- Obtain both PATS keys from the customer and follow the procedure within this pinpoint test using one PATS key, then the other. If the customer only has one PATS key, it will be necessary to cut a new PATS key.
- If it is necessary to cut a new PATS key, program the new PATS key. Refer to Key Programming Using Diagnostic Equipment .
- Key in ON position.
- Clear the PCM DTCs.
- Key in OFF position.
- Key in ON position.
- Retrieve the PCM DTCs.
- Using all the existing keys, then the new key, is DTC B1600 present?
1. YES : If DTC B1600 was present for all existing keys and the new key, go to B3.
  If DTC B1600 was not present for all keys, the key may be damaged and should be replaced. CUT a new key to replace the damaged key. PROGRAM the new PATS key. REFER to Key Programming Using Diagnostic Equipment . CLEAR the DTCs. REPEAT the self-test.
2. NO : If DTCs other than PATS DTCs are retrieved, REFER to the Introduction - Gasoline Engines article. If no PATS DTCs are retrieved, the system is OK. The concern may have been caused by interference from another object.
B3 INSTALL A NEW PATS TRANSCEIVER
NOTE: Replacement of the PATS transceiver does not require the PATS keys to be programmed into the PCM again.

NOTE: Do not use the PATS key that may have been programmed in Step B2.
- Key in OFF position.
- Install a new PATS transceiver. Refer to Passive Anti-Theft System (PATS) Transceiver .
- Key in ON position.
- Clear the PCM DTCs.
- Key in OFF position.
- Key in ON position.
- Turn the key to the ON position using an existing customer PATS key.
- Retrieve the PCM DTCs.
- Is DTC B1600 retrieved?
1. YES : Go to B4.
2. NO : The system is OK.
B4 CHECK FOR CORRECT PCM OPERATION
NOTE: When a new PCM is installed, the PATS keys must be programmed into the PCM.
- Disconnect all the PCM connectors.
- Check for:
  - corrosion
  - damaged pins
  - pushed-out pins
- Connect all the PCM 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 PCM. REFER to ELECTRONIC ENGINE CONTROLS article. PROGRAM the PATS keys into the PCM. REFER to Key Programming Using Diagnostic Equipment . 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.