Back to 2017 Chevrolet Impala

2017 CHEVROLET IMPALA

2.5L I4 EcotecAWDAUTOMATICgas
Repairs0Labor990Torque7715Fluid15DTC1938Battery2Maintenance0Recalls0
P1629high severityPowertrain

Theft Deterrent Cranking Signal

on 2017 Chevrolet Impala 2.5L I4 Ecotec · AWD

What this code means

The PCM is not receiving the expected cranking signal through the theft deterrent system during startup. The system cannot verify that the vehicle is being started with the correct key.

Symptoms

  • Vehicle will not start
  • Security light on
  • Engine cranks but does not run
  • Intermittent no-start

Common causes

  • Faulty ignition switch
  • Passlock sensor issue
  • BCM malfunction
  • Wiring fault in cranking signal circuit

Diagnostic steps

  1. Check security system status
  2. Test cranking signal at PCM
  3. Inspect ignition switch operation
  4. Test Passlock sensor
  5. Check BCM communication

Repair notes

Test ignition switch and Passlock sensor. Perform security relearn if needed.

Other Powertrain codes on this vehicle

Building an app?
Free API access to all this data — 50 requests/day, no card required.
Get an API key →
Run a shop?
Manage repairs, estimates, and customers with ShopBase — $249/mo, all features included.
Try ShopBase →