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 MANUALSGMC1991S15 JIMMY 2D UTILITY, RWD, STANDARDREPAIR AND DIAGNOSIS (SINGLE PAGE)ENGINE PERFORMANCETHEORY AND OPERATIONENGINE CONTROLS - THEORY & OPERATIONCOMPUTERIZED ENGINE CONTROLS (GASOLINE)ELECTRONIC CONTROL MODULE (ECM)POWER SUPPLY
1991 GMC S15 Jimmy 2D Utility, RWD, Standard
Power Supply
1991 GMC S15 Jimmy 2D Utility, RWD, StandardSECTION Power Supply
Power for ECM reference output signals (5 volts) and control devices (12 volts) is received from the battery through ignition circuit when ignition switch is in ON position. Keep-alive memory power is received directly from the battery.
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.