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2002 CADILLAC DEVILLE
4.6L V8 Northstar•FWD•AUTOMATIC•gas
5 active safety recalls on this vehicle — view recalls
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Repairs0Labor491Torque4250Fluid7DTC1027Battery1Maintenance0Recalls5
P1634high severityPowertrain

Ignition 1 Power Circuit Low Voltage

on 2002 Cadillac DeVille 4.6L V8 Northstar · FWD

What this code means

The PCM detected low voltage on the Ignition 1 power supply circuit.

Symptoms

  • Check Engine Light
  • Engine stalling
  • Erratic gauges
  • Multiple system malfunctions

Common causes

  • Faulty ignition switch
  • Blown Ignition 1 fuse
  • Corroded connections
  • Damaged wiring in ignition circuit

Diagnostic steps

  1. Test Ignition 1 circuit voltage at PCM
  2. Check Ignition 1 fuse
  3. Test ignition switch
  4. Inspect wiring and connectors

Repair notes

Check fuse and ignition switch. Repair wiring as needed.

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