Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSCHEVROLET1994K 2500 SUBURBAN 4WD V8-454 7.4LREPAIR AND DIAGNOSISRELAYS AND MODULESRELAYS AND MODULES - POWERTRAIN MANAGEMENTRELAYS AND MODULES - IGNITION SYSTEMIGNITION CONTROL MODULETESTING AND INSPECTION
1994 Chevrolet K 2500 Suburban 4WD V8-454 7.4L
Ignition Control Module: Testing and Inspection
1994 Chevrolet K 2500 Suburban 4WD V8-454 7.4LSECTION Testing and Inspection
AllData Editor Note: OE does not supply any Component testing for the Ignition Control Module. The way OE has you Test an Ignition Module is by checking for proper inputs. If all the inputs are there, and the module doesn't either fire a coil, and/or referance the Engine Control Module (to energize an injector), the Ignition Module is bad.
If the vehicle cranks for at least 5 seconds and the Engine Control Module doesn't see a referance signal, some Models will set a code, 42 (Hard) or 12 (Soft). If your vehicle has one of these codes, begin with the Diagnostic System Check in Computers and Controls, then proceed to the Trouble Code Chart (Yes, some vehicles have a DTC Chart for Code 12).
If the vehicle does not set a code, begin with the Diagnostic System Check, and it will send you to a Diagnostic Chart that checks for your particular condition.
These types of tests are found under Computers and Control Systems. Testing and Inspection
RENDER: 1.0x
NO RELATED
Recommended Tools & Savings
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
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.