Topic: need help lots of codes in the pcm

[Dynamic4x4]

I have a 95 yj that is throwing codes for lose of battery power, oxygen sensor-lean condition, fuel injection control, MAT Sensor, oxygen sensor or circuit, and engine running to cool.  i am pretty sure that the runing to cool is becouse my fan runs constantly (im stationed overseas and still need to get a thermostat and wire everything up).  The oxygen sensor is also less than 500 miles old.  Im just not sure what caused the codes battery has not been disconnected or went dead in atleast the past 2000 miles so that is confuseing aswell.  The jeep runs normal just finaly decided i should try to get the light off.  i would greatly appreciate any help or ideas on this

[sharpxmen]

I have a 95 yj that is throwing codes for lose of battery power, oxygen sensor-lean condition, fuel injection control, MAT Sensor, oxygen sensor or circuit, and engine running to cool.  i am pretty sure that the runing to cool is becouse my fan runs constantly (im stationed overseas and still need to get a thermostat and wire everything up).  The oxygen sensor is also less than 500 miles old.  Im just not sure what caused the codes battery has not been disconnected or went dead in atleast the past 2000 miles so that is confuseing aswell.  The jeep runs normal just finaly decided i should try to get the light off.  i would greatly appreciate any help or ideas on this

reset the 'puter first, then when you get the new CEL check the codes right away. These codes you're seeing could be old codes.

lean condition could mean lack of fuel pressure or an injector not firing (opening to be more specific).

[Dynamic4x4]

thanks i will try that in the morning is there any way to reset it other than just unhooking the battery?

[FourbangerYJ]

thanks i will try that in the morning is there any way to reset it other than just unhooking the battery?

Remove the + battery cable from the battery and hold it on the - cable for about 30 seconds.

[Dynamic4x4]

ok i cleared out the codes and now it is just saying the code for the MAT sensor so im going to go ahead and order a new sensor but when i was looking at it i noticed the coolant sensor that is at the back of the head had broken off is this the sensor that controls the gauge?

[sharpxmen]

ok i cleared out the codes and now it is just saying the code for the MAT sensor so im going to go ahead and order a new sensor but when i was looking at it i noticed the coolant sensor that is at the back of the head had broken off is this the sensor that controls the gauge?

that's the one for the gauge, the one on the thermostat housing is for the PCM. MAT i take is manifold air temperature and would be in the manifold showhere 1/2 way on the run close to the firewall. Replace this one and then reset the 'puter again and see if you get more codes.

[Dynamic4x4]

will do thanks for the help

[Torch_Ind]

that's the one for the gauge, the one on the thermostat housing is for the PCM. MAT i take is manifold air temperature and would be in the manifold showhere 1/2 way on the run close to the firewall. Replace this one and then reset the 'puter again and see if you get more codes.