U0167

U0167 means the PCM or BCM has lost communication with the immobilizer module (sometimes called SKIM, PATS, IMMO, or TDM depending on manufacturer). On most platforms the immobilizer is what authorizes the engine to start by validating the key transponder against a stored ID — when comms drop, the vehicle typically cranks but does not start, or starts and stalls within 2 seconds. The diagnostic order: (1) Scan every module first to confirm whether U0167 is alone or part of a larger bus-comm fault — U0167 plus U0140/U0100 means CAN-bus issue, not immobilizer issue. (2) Pull the steering-column shroud and inspect the antenna ring around the ignition lock cylinder — the antenna is a small coil that reads the transponder; broken solder joints on the antenna pigtail are common on 100k+ mile vehicles. The antenna typically tests at 5-25 ohms across the coil at key-off. (3) Check power and ground at the immobilizer module connector before condemning the module; immobilizers typically pull constant 12V plus ignition-switched 12V and at least one ground. Critical misdiagnosis caveat: reflash the key/PCM before condemning either module — Ford PATS, GM PassLock, and Chrysler SKIM systems all support a re-pair procedure through the OEM scan tool (or capable aftermarket like Autel IM608, Topdon Phoenix), and a dealer re-pair runs $0-$150 vs. a $400-$800 immobilizer module replacement that still requires programming.

Vehicle-specific patterns: 2003-2008 Chrysler/Dodge/Jeep products with SKIM (Sentry Key Immobilizer Module) throw U0167 from SKIM-to-PCM CAN failure on the PCI bus — the SKIM lives in the steering column and dies from heat soak. 2005-2014 Ford F-150/Mustang/Escape with PATS throws U0167 from the transceiver antenna ring around the ignition cylinder loosening or shorting; symptoms include theft-light flashing and no-start, and the fix is a $40-$120 antenna ring. 2007-2013 GM trucks (Silverado, Tahoe, Suburban) running PassLock or Passkey III throw U0167 from BCM-to-PCM comm failure after aftermarket remote-start installation that tapped into the wrong wire. 2008-2014 Hyundai/Kia Genesis, Sonata, and Sorento commonly throw U0167 from a known SMARTRA (Smart Transponder) module failure that requires dealer key re-coding. Estimated repair: $0 (key re-pair) to $1,000 (immobilizer module replacement plus key programming).