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.
1995 Jeep Wrangler S, AutomaticFACTORY OEM SERVICE PROCEDURE
Engine Controls - Basic Testing - 4.0L
- Introduction
- Computerized Engine Controls
- Powertrain Control Module (Pcm)
- Input Devices
- Notes
- A/C Pressure Switch & Evaporator Switch
- Generator
- Automatic Shutdown (ASD) Relay Input Signal
- Battery Voltage Signal
- Brake Switch
- Camshaft Position (CMP) Sensor
- Crankshaft Position (CKP) Sensor
- Engine Coolant Temperature (ECT) Sensor
- Heated Oxygen Sensor (HO2S)
- Ignition Circuit
- Intake Air Temperature (IAT) Sensor
- Manifold Absolute Pressure (MAP) Sensor
- Park/Neutral Switch
- Power Steering Pressure Switch
- Serial Communications Interface (SCI) Receive
- Cruise Control Switches
- Throttle Position (TP) Sensor
- Vehicle Speed Sensor (VSS)
- Vehicle Theft Alarm (Grand Cherokee)
- Output Signals
- Notes
- A/C Compressor Clutch Relay
- Generator Light
- Automatic Shutdown (ASD) Relay
- Cruise Control Servo
- EGR Valve Control Solenoid
- Evaporative Emission System
- Fuel Injectors
- Fuel Pump Relay
- Idle Air Control (IAC) Motor
- Ignition Coil
- Injection Timing
- Malfunction Indicator Light (MIL)
- Radiator Cooling Fan Relay
- Serial Communication Interface (SCI) Transmit
- Upshift Indicator Light (M/T)
- Fuel System
- Ignition System
- Emission Systems
- Self-Diagnostic System
- Miscellaneous Controls
- Wiring Diagrams
Factory Service Tools
Use the Manual With the Right Hardware
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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.