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P1626CriticalElectrical

P1626: Theft Deterrent Fuel Enable Signal Lost

2 vehicles · 2 makes · $150-$600 repair

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Most Reported On

2000-2005Chevrolet Impala1999-2005Pontiac Grand Am

P1626 is an OBD-II diagnostic trouble code meaning “Theft Deterrent Fuel Enable Signal Lost.” This is a manufacturer-specific (commonly GM) anti-theft code indicating that the fuel-enable signal from the theft-deterrent system was lost or not received by the engine control module. As a security measure, the immobilizer or body control module must send a valid signal authorizing the ECM to deliver fuel; without it, the ECM disables fueling so a stolen vehicle cannot be driven. The result is usually an engine that cranks but will not start, often with a security light on. It generally points to a security-system communication or authentication problem rather than a fuel or engine mechanical fault. This code is most commonly reported on 2000-2005 Chevrolet Impala, and 1999-2005 Pontiac Grand Am, with repair costs ranging from $150 to $600.

On This Page

  • Common Causes
  • Repair Cost
  • Vehicles (2)
  • Related Codes
  • FAQ
  • Sources (6)

Makes

  • Chevrolet1
  • Pontiac1
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Common Causes

1Communication fault between the body control module and ECM
2Faulty or unrecognized key/transponder or immobilizer issue
3Damaged wiring or connectors in the theft-deterrent circuit
4Faulty body control module (BCM)
5Faulty or improperly programmed engine control module
6Loss of power or ground to a security-system module
7Modules not properly relearned after a battery or part replacement

Typical Repair Cost

$150 - $600

Based on 2 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.

Diagnostic Tools

To diagnose P1626, you'll need an OBD-II scanner. Here are our recommendations at every price point.

Budget Pick$10–$20

ANCEL AD310 Classic OBD-II Scanner

by ANCEL

A simple, affordable code reader that reads and clears check engine codes. Great for quick diagnostics on any OBD-II vehicle (1996+).

  • Read & clear engine codes
  • View freeze frame data
  • I/M readiness status
  • No batteries or app needed
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Best Value$90–$120

BlueDriver Pro Bluetooth Scanner

by BlueDriver

Bluetooth OBD-II scanner with a free companion app. Provides enhanced diagnostics, smog readiness, and repair reports sourced from a database of verified fixes.

  • Enhanced diagnostics (ABS, SRS, transmission)
  • Repair Reports with verified fixes
  • Smog check readiness
  • Free app (iOS & Android)
Check Price on Amazon
Advanced$180–$230

LAUNCH CRP123X OBD-II Scanner

by LAUNCH

A professional-grade handheld scanner that reads all four major systems (engine, transmission, ABS, SRS) with live data streaming and graphing.

  • Engine, transmission, ABS, SRS diagnostics
  • Live data stream & graphing
  • AutoVIN for vehicle identification
  • Free lifetime updates via Wi-Fi
Check Price on Amazon
Professional$350–$450

Autel MaxiCOM MK808S Diagnostic Tool

by Autel

Shop-level diagnostic tablet with bi-directional control, active tests, and full system coverage. Ideal for serious DIYers and small shops.

  • All-system diagnostics (25+ modules)
  • Bi-directional control & active tests
  • Oil reset, EPB, BMS, TPMS, injector coding
  • 7-inch touchscreen with Android OS
Check Price on Amazon

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Vehicles Affected (2)

Chevrolet P1626 page →
ImpalaCritical

Passlock Security System No-Start Condition

2000-2005$150-$6000 reports
Pontiac P1626 page →
Grand AmCritical

Passlock Anti-Theft System False Activation Causing No-Start

1999-2005$250-$5500 reports

Related Codes (8)

B1A13Battery Voltage Low (Body Module)B2960Key/Immobilizer Communication ErrorP0562System Voltage LowP0620Generator Control Circuit MalfunctionP0657Actuator Supply Voltage A Circuit/OpenP0A09DC/DC Converter Status Circuit LowP0A0AHigh Voltage System Interlock CircuitP0A1AMotor Generator A - Performance

FAQ

What does P1626 mean?

P1626 stands for "Theft Deterrent Fuel Enable Signal Lost." This is a manufacturer-specific (commonly GM) anti-theft code indicating that the fuel-enable signal from the theft-deterrent system was lost or not received by the engine control module. As a security measure, the immobilizer or body control module must send a valid signal authorizing the ECM to deliver fuel; without it, the ECM disables fueling so a stolen vehicle cannot be driven. The result is usually an engine that cranks but will not start, often with a security light on. It generally points to a security-system communication or authentication problem rather than a fuel or engine mechanical fault.

What are the most common causes of P1626?

The most common causes of P1626 are: Communication fault between the body control module and ECM, Faulty or unrecognized key/transponder or immobilizer issue, Damaged wiring or connectors in the theft-deterrent circuit, Faulty body control module (BCM), Faulty or improperly programmed engine control module, Loss of power or ground to a security-system module, Modules not properly relearned after a battery or part replacement. The specific cause varies by vehicle.

How much does it cost to fix P1626?

Repair costs for P1626 range from $150 to $600, depending on the vehicle and root cause.

Which vehicles are affected by P1626?

Au7o has documented P1626 across 2 vehicle models from 2 manufacturers: Chevrolet, Pontiac.

Sources (6)

  • ForumReddit r/MechanicAdvice thread discussing 2003 Chevy Impala Passlock No-Start Condition
  • article2003 Pontiac Grand Am Passlock Problem, Won't Start And Security Light Is Blinking: 25 Complaints
  • ForumSecurity light on Pontiac Grand Am — Car Talk Community (2004 Grand Am, Passlock ignition switch failure)
  • ForumPontiac Grand Am Security Passlock Problems — Edmunds Car Forums (23+ pages)
  • articleNo Start Due to Failed Passlock Sensor: Pontiac Grand Am Electrical System — RepairPal
  • NHTSANHTSA complaints, 2002 Pontiac Grand Am — multiple ODI records for Passlock/security-light no-start (10898347, 10622496, 10503032, 10726457)

Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.

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