Normal Operation

The Passive Anti-Theft System (PATS) uses a visual anti-theft indicator located in the Instrument Cluster (IC). This indicator proves out for 3 seconds when the key is turned to the ON or START position under normal operation. If there is a PATS  concern, this indicator either flashes rapidly or glows steadily (for more than 3 seconds) when the key is turned to the ON or START position. PATS  also flashes the anti-theft indicator every 2 seconds at key off to act as a visual theft deterrent. The anti-theft indicator operation is controlled by the IC  .

If DTC U2510 is present, refer to DTC CHARTS  in this service information.

• DTC P1602 (Immobilizer/ ECM  Communication Error) - sets in continuous memory when the PCM does not receive any recent communication from the PATS  module. On this vehicle, the PATS  function is contained in the Instrument Cluster (IC). A parameter reset should resolve this DTC.
• DTC U0100 (Lost Communication With ECM  /PCM) - sets in continuous memory only when the IC  loses communication with the PCM and the fault may not be present at the time of testing. This DTC may be caused by a High Speed Controller Area Network (HS-CAN) circuit issue, the IC  or the PCM.
• DTC U2511 (CAN  - Data Mis-Match [Receive Data Does Not Match Expected]) - sets in continuous memory only when the IC  does not receive the expected response from the PCM over the HS-CAN  and the fault may not be present at the time of testing. The data sent by the PCM does not match the data expected by the IC  and this DTC is set. This DTC can be caused by the HS-CAN  circuits between the IC  and the PCM or by either module. This DTC can also be set if the battery voltage is low.

This pinpoint test is intended to diagnose the following: 

• Wiring, terminals or connectors
• Low battery state of charge
• IC 
• PCM