Decoding Your Jeep & Chrysler OBDII Codes: A Comprehensive Guide

Navigating car troubles can be frustrating, especially when the check engine light illuminates in your Jeep or Chrysler vehicle. Fortunately, modern vehicles are equipped with On-Board Diagnostics (OBD) systems that can help pinpoint potential issues. This guide provides a detailed breakdown of how to retrieve and understand OBDII codes in your Chrysler and Jeep models, empowering you with the knowledge to troubleshoot common problems. While this information is a valuable resource for preliminary diagnostics, remember it’s not a substitute for professional repair expertise.

Understanding OBD-I and OBD-II “Key Trick” for Code Retrieval

Chrysler and Jeep vehicles utilize a simple “key trick” to display diagnostic trouble codes without needing a scan tool. The procedure varies slightly depending on whether your vehicle is an older OBDI model or a newer OBDII compliant one.

Retrieving Codes on Older (OBDI) Chrysler & Jeep Models

For older Chrysler and Jeep vehicles, typically pre-1996 models, follow these steps to access the diagnostic codes:

Start with the ignition OFF.
Within five seconds, cycle the ignition key from OFF to ON and back to OFF three times, ending in the ON position. (ON is NOT “Start” and OFF is NOT “Lock”).
Observe the “check engine” light. It will begin to flash a sequence of codes.

Interpreting OBDI Flashes:

Each code is a two-digit number.
Flashes are separated by pauses. For example, code 23 would be FLASH FLASH (pause) FLASH FLASH FLASH (longer pause).
The system will not flash more than 9 times consecutively in a single digit.
Code 55 indicates “end of codes” and is a normal signal that the system has finished displaying all stored codes.

Important Notes for OBDI Systems:

You may need to engage the parking brake for the codes to display correctly in some models.
Blink spacing on older systems might not be perfectly uniform, so be patient and carefully count the flashes and pauses. If you see a repeating “23 23” pattern, it is likely a single “55” (end of codes).

Retrieving Codes on Newer (OBDII) Chrysler & Jeep Models

For newer Chrysler and Jeep vehicles (generally 1996 and newer OBDII compliant models), use this method:

Insert the key into the ignition.
Press and hold down the odometer reset button.
While holding the button, turn the ignition key to the RUN position. (Do not start the engine).
Release the odometer reset button.

Reading OBDII Codes on the Odometer:

The odometer will go through a self-test sequence, displaying “111111” to “999999”.
It will then display the vehicle’s serial number.
Finally, it will show any stored error codes, often prefixed with a “P” (for Powertrain codes).

Alternative OBDII Retrieval Method:

If the odometer method doesn’t work, you can also try the OBDI “key trick” method on some newer OBDII models.

Chrysler & Jeep OBD-I Trouble Codes

Important! Be aware that code definitions can vary slightly, especially for vehicles around the 1996 transition year. This list is a comprehensive guide but should be used for troubleshooting assistance, not as a definitive repair manual.

11: No ignition reference signal detected during cranking OR timing belt skipped one or more teeth; OR loss of either camshaft or crankshaft position sensor.
12: Battery or computer recently disconnected
13: MAP sensor or vacuum line may not be working
14: MAP sensor voltage below .16V or over 4.96V
15: No speed/distance sensor signal
16: Loss of battery voltage detected with engine running
17: Engine stays cool too long (bad thermostat or coolant sensor?) OR 17 (1985 turbo only): knock sensor circuit
21: Oxygen sensor signal doesn’t change (stays at 4.3-4.5V). Probably bad oxygen sensor
22: Coolant sensor signal out of range – May have been disconnected to set timing
23: Incoming air temperature sensor may be bad
24: Throttle position sensor over 4.96V
25: Automatic Idle Speed (AIS) motor driver circuit shorted or target idle not reached
26: Peak injector circuit voltage has not been reached (need to check computer signals, voltage reg, injectors)
27: Injector circuit isn’t switching when it’s told to (TBI) OR (MPI) injector circuit #1 not switching right OR (turbo) injector circuit #2 not switching right OR (all 1990-) injector output driver not responding – check computer, connections
31: Bad evaporator purge solenoid circuit or driver
32: (1984 only) power loss/limited lamp or circuit OR 32 EGR gases not working (1988) – check vacuum, valve OR 32 (1990-92) computer didn’t see change in air/’fuel ratio when EGR activated – check valve, vacuum lines, and EGR electrical
33: Air conditioning clutch relay circuit open or shorted (may be in the wide-open-throttle cutoff circuit or normal on early 80’s models if you don’t have air conditioning)
34: (1984-86) EGR solenoid circuit shorted or open OR 34 (1987-1991) speed control shorted or open
35: Cooling fan relay circuit open or shorted OR 35 idle switch motor fault – check connections
36: (turbo only) Wastegate control circuit open or shorted
37: Shift indicator light failure, 5-speed OR part throttle lock/unlock solenoid driver circuit (87-89) OR solenoid coil circuit (85-87 Turbo only) OR Trans temperature sensor voltage low (1995 and on)
41: Alternator field control circuit open or shorted
42: Automatic shutdown relay circuit open or shorted OR 42 Fuel pump relay control circuit OR 42 Fuel level unit – no change over miles OR 42 Z1 voltage missing when autoshutdown circuit energized (The Z1 voltage is the voltage of the circuits fed by the autoshutdown relay. This typically includes fuel pump and switched-battery feed to the ignition coil)
43: Peak primary coil current not achieved with max dwell time OR 43 Cylinder misfire OR 43 Problem in power module to logic module interface
44: No FJ2 voltage present at logic board OR 44 Logic module self-diagnostics indicate problem OR 44 Battery temperature out of range
45: Turbo boost limit exceeded (engine was shut down by logic module)
46: Battery voltage too high during charging or charging system voltage too low
47: Battery voltage too low and alternator output too low
51: Oxygen sensor stuck at lean position (this may be tripped by a bad MAP sensor system causing a rich condition. If you get hot rough idle and stalling, especially on deceleration, accompanied by flooded engine and difficulty restarting, that can be a bad MAP sensor causing the O2 sensor to try to compensate. If you get poor cold driveability, stumbling and bucking, and acceptable warm driving with poor gas mileage (a drop of 10 mpg or more), that is usually the O2 sensor. OR 51 Internal logic module fault (’84 turbo only).
52: Oxygen sensor stuck at rich position OR 52 Internal logic module fault (’84 turbo only)
53: Logic module internal problem
54: No sync pickup signal during engine rotation (turbo only) OR 54 Internal logic module fault (’84 turbo only) – or camshaft sensor/distributor timing
55: End of codes
61: “Baro” sensor open or shorted
62: EMR mileage cannot be stored in EEPROM
62: PCM failure SRI mile not stored
63: Controller cannot write to EEPROM
64: Catalytic converter efficiency failure
65: Power steering switch failure
66: No CCD Message From TCM and/or No CCD Message From BCM

Chrysler & Jeep OBD-II Trouble Codes (P-Codes)

OBDII codes are standardized across manufacturers, but this list provides specific context for Chrysler and Jeep vehicles. These codes are typically five-digit codes, starting with a letter. “P” codes, listed below, refer to Powertrain related issues (engine and transmission).

P030: Sensor heater relay problem
P036: Sensor heater relay problem
P0106: MAP sensor voltage out of range detected at startup
P0107: MAP sensor voltage too low
P0108: MAP sensor voltage too high
P0112: Intake air temperature sensor voltage low
P0113: Intake air (charge) temperature sensor voltage high
P0116: Coolant temperature sensor reading doesn’t make sense
P0117: Engine coolant temperature sensor voltage low
P0118: Engine coolant temperature sensor voltage high
P0121: Throttle position sensor and MAP sensor disagree with each other
P0122: Throttle position sensor voltage low
P0123: Throttle position sensor voltage high
P0125: Taking too long to reach proper operating temperature and switch to energy-efficient mode
P0130: Sensor heater relay problem
P0130: O2 Sensor Circuit Malfunction (Bank 1 Sensor 1)
P0131: O2 Sensor Circuit Low Voltage (Bank 1 Sensor 1)
P0132: O2 Sensor Circuit High Voltage (Bank 1 Sensor 1)
P0133: O2 Sensor Circuit Slow Response (Bank 1 Sensor 1)
P0134: O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 1)
P0135: O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 1)
P0136: O2 Sensor Circuit Malfunction (Bank 1 Sensor 2)
P0137: O2 Sensor Circuit Low Voltage (Bank 1 Sensor 2)
P0138: O2 Sensor Circuit High Voltage (Bank 1 Sensor 2)
P0139: O2 Sensor Circuit Slow Response (Bank 1 Sensor 2)
P0140: O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 2)
P0141: O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 2)
P0142: O2 Sensor Circuit Malfunction (Bank 1 Sensor 3)
P0143: O2 Sensor Circuit Low Voltage (Bank 1 Sensor 3)
P0144: O2 Sensor Circuit High Voltage (Bank 1 Sensor 3)
P0145: O2 Sensor Circuit Slow Response (Bank 1 Sensor 3)
P0146: O2 Sensor Circuit No Activity Detected (Bank 1 Sensor 3)
P0147: Oxygen sensor heater element not working properly (this device helps to reduce emissions more quickly)
P0151: Oxygen sensor voltage problem – short circuit to ground?
P0152: Oxygen sensor voltage problem – short circuit to active 12V?
P0153: Oxygen sensor response too slow
P0154: Oxygen sensor does not show either a rich or lean condition – may need replacement
P0155: Oxygen sensor heater element not working properly (this device helps to reduce emissions more quickly)
P0157: Oxygen sensor voltage problem – short circuit to ground?
P0158: Oxygen sensor voltage problem – short circuit to active 12V?
P0159: Oxygen sensor response too slow
P0160: Oxygen sensor does not show either a rich or lean condition – may need replacement
P0161: Oxygen sensor heater element not working properly (this device helps to reduce emissions more quickly)
P0171: The oxygen sensor is saying that the system air/fuel mix is far too lean (too much fuel is being added as a correction).
P0172: The oxygen sensor is saying that the system air/fuel mix is far too rich (too much air is being added as a correction).
P0174: The oxygen sensor is saying that the system air/fuel mix is far too lean (too much fuel is being added as a correction).
P0175: The oxygen sensor is saying that the system air/fuel mix is far too rich (too much air is being added as a correction).
P0176: Flex fuel sensor can’t be seen
P0178: Flex fuel sensor problem
P0179: Flex fuel sensor problem
P0182: Compressed natural gas temperature sensor problem
P0183: Compressed natural gas temperature sensor problem
P0201: Injector #1 control circuit problem (open or shorted)
P0202: Injector #2 control circuit problem (open or shorted)
P0203: Injector #3 control circuit problem (open or shorted)
P0204: Injector #4 control circuit problem (open or shorted)
P0205: Injector #5 control circuit problem (open or shorted)
P0206: Injector #6 control circuit problem (open or shorted)
P0207: Injector #7 control circuit problem (open or shorted)
P0208: Injector #8 control circuit problem (open or shorted)
P0300: Misfire detected in multiple cylinders.
P0301: Misfire detected in cylinder #1.
P0302: Misfire detected in cylinder #2.
P0303: Misfire detected in cylinder #3.
P0304: Misfire detected in cylinder #4.
P0305: Misfire detected in cylinder #5.
P0306: Misfire detected in cylinder #6.
P0307: Misfire detected in cylinder #7
P0308: Misfire detected in cylinder #8.
P0320: Crankshaft position sensor reference signal cannot be found while the engine is cranking.
P0325: Knock sensor (#1) signal is wrong.
P0330: Knock sensor (#2) signal is wrong.
P0340: No camshaft signal being received by the computer
P0350: A coil is drawing too much current.
P0351: Coil #1 is not reaching peak current at the right time
P0352: Coil #2 is not reaching peak current at the right time
P0353: Coil #3 is not reaching peak current at the right time
P0354: Coil #4 is not reaching peak current at the right time
P0355: Coil #5 is not reaching peak current at the right time
P0356: Coil #6 is not reaching peak current at the right time
P0357: Coil #7 is not reaching peak current at the right time
P0358: Coil #8 is not reaching peak current at the right time
P0401: A required change in air/fuel mixture was not detected during diagnostic test.
P0403: An problem was detected in the EGR solenoid control circuit.
P0404: The EGR sensor’s reported position makes no sense
P0405: EGR position sensor voltage wrong.
P0406: EGR position sensor voltage wrong.
P0412: The secondary air solenoid control circuit seems bad (this is used for the aspirator).
P0420: The catalyst seems inefficient (#1).
P0432: The catalyst seems inefficient (#2).
P0441: Evaporative purge flow system not working properly
P0442: A leak has been detected in the evaporative system!
P0443: Evaporative purge flow system solenoid not working properly
P0455: A large leak has been detected in the evaporative system!
P0456: A small leak has been detected in the evaporative system!
P0460: The fuel level sender is not reporting any change over a long distance. Something seems wrong.
P0461: The fuel level sender is not reporting any change over a long time. Something seems wrong.
P0462: Fuel level sender voltage wrong.
P0463: Fuel level sender voltage wrong.
P0500: Haven’t heard from the speed sensor lately.
P0505: The idle speed air control motor doesn’t seem to be working correctly.
P0522: Oil pressure sensor problems
P0523: Oil pressure sensor problems
P0551: The power steering switch may not be working. (Neons: high pressure is showing up at high speed)
P0600: Oh-oh! The coprocessors aren’t talking to each other within the computer!
P0601: Internal computer error!
P0604: Internal computer error! (RAM check)
P0605: Internal computer error! (ROM)
P0615: Starter relay circuit problem
P0622: Generator field control problem
P0645: A/C clutch relay circuit problem.
P0700: The automatic transmission computer or Aisin computer has a problem – ask it what’s going on. I don’t know.
P0703: Brake switch circuit information seems wrong.
P0711: Based on the transmission temperature and its operations, it looks like the transmission temperature sensor’s gone bad.
P0712: Transmission fluid temperature sensor voltage wrong.
P0713: Transmission fluid temperature sensor voltage wrong.
P0720: The Output Shaft Speed Sensor doesn’t match the reported vehicle speed.
P0740: The engine’s running faster than it should for these speeds, so I think thetorque converter clutch lock-up system is bad
P0743: Torque converter clutch (part throttle unlock) solenoid circuit problem – shift solenoid C electrical fault
P0748: Governor Pressure Solenoid circuit problem (Transmission relay circuit problem in Jeep RE transmissions)
P0751: Overdrive override switch has been pressed for over five minutes. Just thought you should know.
P0753: Overdrive solenoid control circuit problem (transmission relay circuit in Jeep RE transmissions.)
P0756: Shift solenoid B (2-3) fault
P0783: The overdrive solenoid can’t go from 3rd gear to the overdrive gear.
P0801: Transmission reverse gear lockout solenoid circuit problem!
P0833: Problem with the clutch-released switch circuit?
P1192: Inlet air temperature sensor voltage is wrong
P1193: Inlet air temperature sensor voltage is wrong
P1194: Oxygen sensor heater performance is faulty
P1195: Oxygen sensor is slow
P1196: The oxygen sensor switched too slowly (bank 2).
P1197: The oxygen sensor switched too slowly (bank 1).
P1198: Radiator coolant temperature sensor voltage is wrong.
P1199: Radiator coolant temperature sensor voltage is wrong.
P1281: The engine is staying cold too long – check your thermostat.
P1282: The fuel pump relay circuit seems to be having a problem.
P1288: The intake manifold short runner tuning valve circuit seems to be having a problem.
P1289: There’s a problem in the manifold tuning valve solenoid control circuit.
P1290: Compressed natural gas system pressure is too high
P1291: The heated air intake sensor does not seem to be working.
P1292: Natural gas pressure sensor issue
P1293: Natural gas pressure sensor issue
P1294: Can’t get to target engine speed, check for vacuum leaks and idle speed motor issues.
P1295: The throttle position sensor doesn’t seem to be getting enough electricity.
P1296: The MAP sensor doesn’t seem to be getting enough electricity.
P1297: The MAP sensor doesn’t change its reading when the engine is running!
P1298: During wide-open throttle, the engine runs lean.
P1299: MAP Sensor and Throttle Position Sensor signals don’t match, check for a vacuum leak.
P1388: Auto shutdown relay circuit problems?
P1389: No Z1 or Z2 voltage seen by the computer when the auto shutdown relay is used.
P1390: Cam and crank signals don’t match – did the timing belt skip a tooth?
P1391: Sometimes, I can’t see the crank or cam sensor signal.
P1398: I can see the Crank Sensor’s signal when I prepare for Misfire Diagnostics. Try replacing it.
P1399: Problem in the Wait to Start Lamp circuit – (diesels only?)
P1403: EGR position sensor not getting (enough) voltage.
P1476: Too little secondary air injection during aspirator test.
P1477: Too much secondary air injection during aspirator test.
P1478: Battery temperature sensor voltage wrong.
P1479: Transmission fan relay circuit problems?
P1480: PCV solenoid circuit problems?
P1481: Transmission RPM pulse generator signal for misfire detection seems wrong.
P1482: Catalyst temperature sensor circuit shorted low.
P1483: Catalyst temperature sensor circuit shorted high.
P1484: The catalyst seems to be overheating!
P1485: Air injection solenoid circuit problems.
P1486: Pinched or blocked hose in the evaporative hose system.
P1487: Control circuit of the #2 high-speed radiator fan control relay is having problems.
P1488: Auxiliary 5-volt sensor feed is too low.
P1489: High speed radiator fan control circuit problem.
P1490: Low speed radiator fan control circuit problem.
P1491: Radiator fan control circuit problem (may be solid state relays as well as other circuits).
P1492: Ambient or battery temperature sensor voltage wrong
P1493: Ambient or battery temperature sensor voltage wrong
P1494: Leak Detection Pump (LDP) pressure switch problem – electrical or the pump itself.
P1495: Leak Detection Pump (LDP) pressure switch problem – the solenoid circuit.
P1496: Sensor feed is below an acceptable limit. (under 4v for 4 seconds – should be 5v).
P1498: High speed radiator fan control circuit problem. (#3 control relay)
P1594: Voltage too high in charging system.
P1595: Speed control vacuum or vent solenoid control circuits shorted or lost.
P1596: Speed control switch always high
P1597: Speed control switch always low
P1598: A/C pressure sensor voltage high
P1599: A/C pressure sensor voltage low
P1681: No messages received from the cluster control module (dashboard computer).
P1682: Charging system doesn’t seem to be working well. Check alternator, etc.
P1683: Speed control servo power control circuit problem.
P1684: The battery has been disconnected within the last 50 starts.
P1685: Invalid key received from the Smart Key Immobilizer Module.
P1686: No messages received from the Smart Key Immobilizer Module.
P1687: No messages received from the Mechanical Instrument Cluster module.
P1693: The companion engine control module has shown a fault.
P1694: No messages received from the powertrain control module-Aisin transmission.
P1695: No messages received from the body control module.
P1696: Unsuccessful attempt to write to an EEPROM location!
P1697: Unsuccessful attempt to update Service Reminder Indicator (SRI or EMR) mileage!
P1698: No messages received from the electronic transmission control module or the Aisin transmission controller.
P1719: Transmission 2-3 gear lockout solenoid control circuit problem.
P1740: Either the tcc solenoid or overdrive solenoid systems doesn’t seem to be making much sense.
P1756: Transmission control pressure not equal to target. (Mid pressure problem)
P1757: Transmission control pressure not equal to target. (Zero pressure problem)
P1762: The Governor Pressure Sensor input was too high or too low for 3 consecutive park/neutral calibrations.
P1763: The Governor Pressure Sensor input is too high
P1764: The Governor Pressure Sensor input is too low.
P1765: Open or short in the Transmission Relay control circuit.
P1899: The Park/Neutral switch seems to be stuck!

Important Note: When the computer detects a major system failure, it may activate “Limp In” mode. This is a safety feature that allows you to drive the car to a mechanic by estimating data to compensate for sensor failures. A common symptom of “Limp In” mode is the loss of third and/or fourth gear in automatic transmissions.

Disclaimer: This code list is compiled from various sources and is intended as a guide for troubleshooting, not a definitive repair manual. Accuracy is not guaranteed, and codes can sometimes be misleading. Always consult a certified mechanic for diagnosis and repairs. Code readers and professional diagnostic tools provide more accurate and detailed information than the “key trick” method.

This information is provided by cardiagnosticnearme.com, your resource for automotive diagnostic information.