A DRB scan tool is the ideal diagnostic tool for a 1995 Jeep Wrangler, but it can be expensive. Fortunately, there’s a built-in diagnostic system for retrieving engine codes without any special tools. This system utilizes the Check Engine Light (CEL) to communicate trouble codes. This article explains how to access these codes and provides a comprehensive list of their meanings.
Reading Trouble Codes on a 1995 Jeep Wrangler
Retrieving diagnostic trouble codes (DTCs) on your 1995 Jeep Wrangler is a straightforward process:
- Key On/Off Cycle: Turn the ignition key on and off three times in rapid succession, ending with the key in the ‘on’ position. Do not start the engine.
- Observe the CEL: The CEL will begin to flash. Long pauses separate distinct codes, while shorter flashes represent the individual digits of each code.
- Record the Codes: Write down the flashing sequences. Each code consists of two digits. For example, two flashes followed by a pause and then three flashes represent code 23.
- Code 55: The sequence ending with a 55 indicates the end of the diagnostic codes.
- Ignore Code 33: If your Wrangler doesn’t have air conditioning, disregard code 33.
1995 Jeep Wrangler OBDI Codes
Below is a list of common OBDI codes for your 1995 Jeep Wrangler and their potential meanings:
- 11: No ignition reference signal (cranking) / Timing belt skipped / Camshaft or crankshaft position sensor issue.
- 12: Battery or computer recently disconnected.
- 13: MAP sensor or vacuum line problem.
- 14: MAP sensor voltage out of range (below 0.16V or above 4.96V).
- 15: No speed/distance sensor signal.
- 16: Loss of battery voltage (engine running).
- 17: Engine cooling issue (thermostat, coolant sensor) / Knock sensor circuit (1985 turbo only).
- 21: Oxygen sensor signal unchanging (around 4.3-4.5V). Likely a bad oxygen sensor.
- 22: Coolant sensor signal out of range.
- 23: Intake air temperature sensor issue.
- 24: Throttle position sensor voltage above 4.96V.
- 25: Automatic Idle Speed (AIS) motor circuit shorted or target idle not reached.
- 26: Peak injector circuit voltage not reached.
- 27: Injector circuit switching problem.
- 31: Evaporator purge solenoid circuit issue.
- 32: EGR system malfunction.
- 33: A/C clutch relay circuit issue (ignore on non-A/C models).
- 34: EGR solenoid circuit issue (1984-86) / Speed control circuit issue (1987-91).
- 35: Cooling fan relay circuit issue / Idle switch motor fault.
- 36: Wastegate control circuit issue (turbo only).
- 37: Shift indicator light failure (5-speed) / Part throttle lock/unlock solenoid issue / Transmission temperature sensor voltage low (1995 and on).
- 41: Alternator field control circuit issue.
- 42: Automatic shutdown relay circuit issue / Fuel pump relay control circuit issue / Fuel level unit issue.
- 43: Peak primary coil current not reached / Cylinder misfire / Power module to logic module interface problem.
- 44: Logic module issue / Battery temperature out of range.
- 45: Turbo boost limit exceeded (engine shutdown).
- 46: Battery voltage too high (charging) / Charging system voltage too low.
- 47: Battery voltage and alternator output too low.
- 51: Oxygen sensor stuck lean / Internal logic module fault (’84 turbo only).
- 52: Oxygen sensor stuck rich / Internal logic module fault (’84 turbo only).
- 53: Logic module internal problem.
- 54: No sync pickup signal (turbo only) / Internal logic module fault (’84 turbo only) / Camshaft sensor/distributor timing.
- 55: End of codes.
- 61: Barometric pressure sensor issue.
- 62: EMR mileage storage issue / PCM failure.
- 63: Controller cannot write to EEPROM.
- 64: Catalytic converter efficiency failure.
- 65: Power steering switch failure.
Conclusion
While a DRB scan tool offers comprehensive diagnostics, using the built-in system allows you to identify many common problems on your 1995 Jeep Wrangler. Understanding these codes empowers you to troubleshoot issues and determine the necessary repairs. Remember to consult a repair manual for detailed diagnostic procedures and repair instructions.
