General Motors A & C Chart Reference

1991 Pontiac 6000 SESECTION General Motors A & C Chart Reference
GENERAL MOTORS A & C CHART REFERENCE

System or Component Diagnostic Information Location
A1 & A2, "SERVICE ENGINE SOON" Light See DIAGNOSTIC CIRCUIT CHECK
A3, No Start See NO START - ENGINE CRANKS OKAY
A5, Fuel Pump Relay See RELAYS, SOLENOIDS & MOTORS in SYSTEM/COMPONENT TESTS
A7, Fuel System Diagnosis See BASIC FUEL SYSTEM CHECKS
C1, MAP Sensor See ENGINE SENSORS & SWITCHES in SYSTEM/COMPONENT TESTS
C1, Power Steering Pressure Switch See ENGINE SENSORS & SWITCHES in SYSTEM/COMPONENT TESTS
C1, Park/Neutral Switch See ENGINE SENSORS & SWITCHES in SYSTEM/COMPONENT TESTS
C2, Injector Balance Test See FUEL CONTROL in SYSTEM/COMPONENT TESTS
C2, IAC Motor See IDLE CONTROL SYSTEM in SYSTEM/COMPONENT TESTS
C2, ISC Motor See IDLE CONTROL SYSTEM in SYSTEM/COMPONENT TESTS
C3, Canister Purge System See EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM/COMPONENT TESTS
C4F DIS Misfire See DIS MISFIRE - 3.1L (VIN T) "W" BODY - C4F Chart 
C4, EST Ignition Check See BASIC IGNITION SYSTEM CHECKS
C5, ESC Ignition Check See IGNITION SYSTEM in in the SYSTEM/COMPONENT TESTS
C6, Air Injection System See EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM/COMPONENT TESTS
C7, EGR System See EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM/COMPONENT TESTS
C8, Torque Converter Clutch See MISCELLANEOUS ECM CONTROLS in SYSTEM/COMPONENT TESTS
C8, Manual Trans. Shift Lights See MISCELLANEOUS ECM CONTROLS in SYSTEM/COMPONENT TESTS
C10, A/C Clutch Control (1) See MISCELLANEOUS ECM CONTROLS in SYSTEM/COMPONENT TESTS
C12, Electric Cooling Fan Control (2) See MISCELLANEOUS ECM in SYSTEM/COMPONENT TESTS
(1) Covered in the AIR CONDITIONING & HEATING section.
(2) Refer to ENGINE COOLING FAN article in the ENGINE COOLING section.
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.