Code 12 and code 21
- Thread starter foamf1
- Start date
Most of the codes I have seen are like P0012 or P0021 which don't really match anything I could find. How are you getting your codes?
Turning the key on and off 3 times and counting the flashes of the check engine light, the codes also show up in the odometer area.
I'm not sure what those codes mean either, as I am only familiar the style of codes @pagrey mentioned, which would come from an actual OBDII scanner.
However, they may be in the FSM, which you can download for free here:
Jeep Wrangler TJ Factory Service Manuals (FSM) & Technical Documentation
However, they may be in the FSM, which you can download for free here:
Jeep Wrangler TJ Factory Service Manuals (FSM) & Technical Documentation
The 97 codes are a bit odd. Code 12 means that the battery has been disconnected within the last 50 starts (or some number like that). Mine has always popped up even when the battery hasn't been disconnected. 21 is an o2 sensor (most likely upstream).
FWIW....
The Codes - 1997 Models:
11 No crank reference signal detected during engine cranking. Intermittent loss of either camshaft or crankshaft position sensor. CKP sensor target windows have too much variation.
12 Direct battery input to PCM was disconnected within the last 50 Key-on cycles.
13 No difference recognized between the engine MAP reading and the barometric (atmosphere) pressure reading from start-up.
14 MAP sensor input above or below acceptable voltage. 5 volt output to MAP sensor open.
15 No vehicle speed sensor signal detected during road load conditions.
17 Engine did not reach operating temperature within acceptable limits. Engine does not reach 20º F. within 5 minutes with a vehicle speed signal.
21 Upstream oxygen sensor response slower than minimum required switching frequency. Upstream oxygen sensor heating element circuit malfunction. Downstream oxygen sensor heating element circuit malfunction. Downstream oxygen sensor input voltage maintained above the normal operating range. Oxygen sensor voltage too low, tested after cold start. (Upstream or Downstream) Left oxygen sensor input voltage maintained above the normal operating temperature.
22 Engine coolant temperature sensor above or below acceptable voltage.
23 Intake air temperature sensor input above or below acceptable voltage.
24 Throttle position sensor input above or below acceptable voltage. TPS signal does not correlate to MAP sensor.
25 A shorted or open condition detected in one or more of the idle air control motor circuits. Actual idle speed does not equal target idle speed.
27 Injector #3, and/or 4, and/or 5, and/or 6 output driver does not respond properly to the control signal.
31 An open or shorted condition detected in the A/C clutch relay circuit. Insufficient or excessive vapor flow detected during evaporative emission system operation.
33 An open or shorted condition detected in the duty cycle purge solenoid circuit.
34 An open or shorted condition detected in the Speed Control vacuum or vent solenoid circuits. Speed control switch input below the minimum acceptable voltage.
37 Relationship between engine speed and vehicle speed indicates no torque converter clutch engagement. An open or shorted condition detected in the torque converter part throttle unlock solenoid control circuit. Incorrect input state detected for the Park/Neutral switch. Auto only.
41 An open or shorted condition in the generator field control circuit.
42 An open or shorted condition detected in the auto shutdown relay circuit. An open condition detected in the ASD relay output circuit. An open or shorted condition detected in the fuel pump relay control circuit. An open circuit between PCM and fuel gauge sending unit. Circuit shorted to voltage between PCM and fuel gauge sending unit. No movement of fuel level sender detected.
43 Peak primary circuit current not achieved with maximum dwell time. Misfire detected in one or more cylinders 1 thru 6. (4 and 6 cyls.)
44 Battery temperature sensor in voltage above or below acceptable range.
46 Battery voltage sense input above target charging voltage during engine operation.
47 Battery voltage sense input below target charging during engine operation. Also, no significant change detected in battery voltage during active test of generator output circuit.
51 A lean air/fuel mixture has been indicated by an abnormally rich correction factor.
52 A rich air/fuel mixture has been indicated by an abnormally rich correction factor.
53 PCM Internal fault condition detected.
54 No camshaft signal detected during engine cranking.
55 Completion of fault code display on Check Engine lamp.
63 Unsuccessful attempt to write to an EEPROM location by the PCM.
64 Catalyst efficiency below required level. (Same as code 72)
65 Power steering high pressure seen at high speed. (2.5L only)
72 Catalyst efficiency below required level. (Same as code 64)
77 Malfunction detected with poser feed to speed control servo solenoids
The Codes - 1997 Models:
11 No crank reference signal detected during engine cranking. Intermittent loss of either camshaft or crankshaft position sensor. CKP sensor target windows have too much variation.
12 Direct battery input to PCM was disconnected within the last 50 Key-on cycles.
13 No difference recognized between the engine MAP reading and the barometric (atmosphere) pressure reading from start-up.
14 MAP sensor input above or below acceptable voltage. 5 volt output to MAP sensor open.
15 No vehicle speed sensor signal detected during road load conditions.
17 Engine did not reach operating temperature within acceptable limits. Engine does not reach 20º F. within 5 minutes with a vehicle speed signal.
21 Upstream oxygen sensor response slower than minimum required switching frequency. Upstream oxygen sensor heating element circuit malfunction. Downstream oxygen sensor heating element circuit malfunction. Downstream oxygen sensor input voltage maintained above the normal operating range. Oxygen sensor voltage too low, tested after cold start. (Upstream or Downstream) Left oxygen sensor input voltage maintained above the normal operating temperature.
22 Engine coolant temperature sensor above or below acceptable voltage.
23 Intake air temperature sensor input above or below acceptable voltage.
24 Throttle position sensor input above or below acceptable voltage. TPS signal does not correlate to MAP sensor.
25 A shorted or open condition detected in one or more of the idle air control motor circuits. Actual idle speed does not equal target idle speed.
27 Injector #3, and/or 4, and/or 5, and/or 6 output driver does not respond properly to the control signal.
31 An open or shorted condition detected in the A/C clutch relay circuit. Insufficient or excessive vapor flow detected during evaporative emission system operation.
33 An open or shorted condition detected in the duty cycle purge solenoid circuit.
34 An open or shorted condition detected in the Speed Control vacuum or vent solenoid circuits. Speed control switch input below the minimum acceptable voltage.
37 Relationship between engine speed and vehicle speed indicates no torque converter clutch engagement. An open or shorted condition detected in the torque converter part throttle unlock solenoid control circuit. Incorrect input state detected for the Park/Neutral switch. Auto only.
41 An open or shorted condition in the generator field control circuit.
42 An open or shorted condition detected in the auto shutdown relay circuit. An open condition detected in the ASD relay output circuit. An open or shorted condition detected in the fuel pump relay control circuit. An open circuit between PCM and fuel gauge sending unit. Circuit shorted to voltage between PCM and fuel gauge sending unit. No movement of fuel level sender detected.
43 Peak primary circuit current not achieved with maximum dwell time. Misfire detected in one or more cylinders 1 thru 6. (4 and 6 cyls.)
44 Battery temperature sensor in voltage above or below acceptable range.
46 Battery voltage sense input above target charging voltage during engine operation.
47 Battery voltage sense input below target charging during engine operation. Also, no significant change detected in battery voltage during active test of generator output circuit.
51 A lean air/fuel mixture has been indicated by an abnormally rich correction factor.
52 A rich air/fuel mixture has been indicated by an abnormally rich correction factor.
53 PCM Internal fault condition detected.
54 No camshaft signal detected during engine cranking.
55 Completion of fault code display on Check Engine lamp.
63 Unsuccessful attempt to write to an EEPROM location by the PCM.
64 Catalyst efficiency below required level. (Same as code 72)
65 Power steering high pressure seen at high speed. (2.5L only)
72 Catalyst efficiency below required level. (Same as code 64)
77 Malfunction detected with poser feed to speed control servo solenoids
Yes our 1997's are a finnicky bunch. Between the early & later wiring differences and then who knows what else they thought about throwing onto these rigs. Mine is a 01/96 build so one of the first off the assembly line. But there really isn't much left stock on mine so I guess it really doesn't matter.
Can u please explain code 33 an 41 because I have those to plus others but I don't understand what those 2 mean specifically
Sure!
Code 33 refers to an open or shorted condition detected in the duty cycle purge solenoid circuit. The duty cycle purge solenoid is part of the evaporative emission control system, which helps to reduce harmful fuel vapors from being released into the atmosphere. An open or short circuit in this solenoid circuit can indicate a fault with the solenoid itself, the wiring connecting it, or a problem with the PCM (Powertrain Control Module) that controls it.
Code 41 refers to an open or shorted condition in the generator field control circuit. This code is related to the charging system of the vehicle. An open or short circuit in the field control circuit can indicate a fault with the alternator, the wiring connecting it, or a problem with the PCM. It means that there may be an issue with the alternator's ability to properly charge the battery.
When diagnosing these codes, it is important to visually inspect the wiring and connections related to these circuits for any obvious signs of damage or corrosion. If no visual issues are found, further testing with a multimeter and possibly a scan tool may be needed to pinpoint the exact cause of the codes.
Ok so I replaced alternator this wkd an it still reads 12.3 volts with it running an no accessories. Runs like crap going thru gas like crazy an has no power like it's giving it to much fuel. Replaced map sensor also 2 weeks ago. Gives alternator field code . Vacuum to map sensor code which all lines look fine . Ac clutch relay which it doesn't have ac an also low engine temp but it's running around 200
If you have already replaced the alternator and are still experiencing low voltage readings, it's possible that there is an issue with the wiring or connections related to the alternator. Make sure that all the connections are clean and secure, and check for any visible signs of damage or corrosion.
As for the fuel consumption and lack of power, it could be related to the MAP sensor replacement or potentially an issue with the fuel system. Check for any vacuum leaks in the intake system as well as the fuel lines. It's also worth checking the fuel pressure to ensure it's within the correct range.
Regarding the AC clutch relay code, if your vehicle doesn't have AC, it's possible that there is a fault in the wiring or component related to the AC system. However, this shouldn't be causing the issues with power and fuel consumption.
Lastly, the low engine temperature code could be indicating a faulty coolant temperature sensor or thermostat. If the engine temperature is reading higher than 200 degrees, it could be a sign of a faulty sensor or thermostat.
If you have checked all the connections and performed these initial checks without finding any obvious issues, I would recommend bringing your vehicle to a qualified mechanic or using a diagnostic tool with live data to further diagnose the codes and issues you are experiencing.
Being able to see live data with a diagnostic tool will be incredibly helpful.
Ok so the wires coming from the alternator going to a plug connector. Green one is loose an can't tell where it's supposed to go or come from. An other loose one is green an black stripe from other side of connector an it's going nowhere also. Also green one isn't going to anything either. Wiring diagram didn't show green wire so I have no clue what it's for
AI crushing it.
Ive since updated my wiring, but I recall the green one from the alternator is the fusible link. If its not connected to anything then you are not getting any current from the alternator. It should connect to the alternator and to the PDC under the hood (the fuse box). Do you have any photos you can post?
Ive since updated my wiring, but I recall the green one from the alternator is the fusible link. If its not connected to anything then you are not getting any current from the alternator. It should connect to the alternator and to the PDC under the hood (the fuse box). Do you have any photos you can post?
Ok so the green wire is coming from the alternator side but I see nowhere that it would've connected to the alternator. That same wire is loose on the other side of that plug plus the other wire. I'm at a loss cause I don't understand the wiring diagrams very well
Ok so the green wire is coming from the alternator side but I see nowhere that it would've connected to the alternator. That same wire is loose on the other side of that plug plus the other wire. I'm at a loss cause I don't understand the wiring diagrams very well
View attachment 452461
What a mess--that is quite the rats nest. The plug has two greens going into it, and an orange. The orange should be your ground and the greens are your field terminals.