philthy

does the odometer say BUSS if it does you have a bad crank sensor and if the
injectors are not firing thne you have a bad cranksensor and not a bad pcm
pcm failure in jeeps is rear thing but get replaced because people (techs)don't
know any better

jtgreek wrote:

> i have a 98 cherokee ,standard trans that won't start-cranks but has no spark-
> no voltage with a test light
> at the crank sensor harness,cam sensor harness,coil harness.i checked all
> grounds that i know of
> including the ground strap at the back of the head to the firewall-not frayed
> at all.checked grounds by
> pcm under hood,appear ok,checked grounds by coil.appear ok also.jeep was
> starting fine-then i let it sit parked for 2 months-kids got in-left interior
> light on-battery went dead-put in a different battery-cranks fine but won't
> start-thought maybe some of gods little creatures got in there and chewed
> wires-but didn't
> see anything .i know i can't just try a different pcm from bone yard because
> it has to be programmed
> to the vehicle- anyone have any ideas -don't really have the money to take
> to JEEP DEALER for
> repairs.......oh and yes i did unplug and plug in crank sensor-didn't help.

philthy

does the odometer say BUSS if it does you have a bad crank sensor and if the
injectors are not firing thne you have a bad cranksensor and not a bad pcm
pcm failure in jeeps is rear thing but get replaced because people (techs)don't
know any better

jtgreek wrote:

> i have a 98 cherokee ,standard trans that won't start-cranks but has no spark-
> no voltage with a test light
> at the crank sensor harness,cam sensor harness,coil harness.i checked all
> grounds that i know of
> including the ground strap at the back of the head to the firewall-not frayed
> at all.checked grounds by
> pcm under hood,appear ok,checked grounds by coil.appear ok also.jeep was
> starting fine-then i let it sit parked for 2 months-kids got in-left interior
> light on-battery went dead-put in a different battery-cranks fine but won't
> start-thought maybe some of gods little creatures got in there and chewed
> wires-but didn't
> see anything .i know i can't just try a different pcm from bone yard because
> it has to be programmed
> to the vehicle- anyone have any ideas -don't really have the money to take
> to JEEP DEALER for
> repairs.......oh and yes i did unplug and plug in crank sensor-didn't help.

philthy

does the odometer say BUSS if it does you have a bad crank sensor and if the
injectors are not firing thne you have a bad cranksensor and not a bad pcm
pcm failure in jeeps is rear thing but get replaced because people (techs)don't
know any better

jtgreek wrote:

> i have a 98 cherokee ,standard trans that won't start-cranks but has no spark-
> no voltage with a test light
> at the crank sensor harness,cam sensor harness,coil harness.i checked all
> grounds that i know of
> including the ground strap at the back of the head to the firewall-not frayed
> at all.checked grounds by
> pcm under hood,appear ok,checked grounds by coil.appear ok also.jeep was
> starting fine-then i let it sit parked for 2 months-kids got in-left interior
> light on-battery went dead-put in a different battery-cranks fine but won't
> start-thought maybe some of gods little creatures got in there and chewed
> wires-but didn't
> see anything .i know i can't just try a different pcm from bone yard because
> it has to be programmed
> to the vehicle- anyone have any ideas -don't really have the money to take
> to JEEP DEALER for
> repairs.......oh and yes i did unplug and plug in crank sensor-didn't help.

Mike Romain

We were taught in electronics school that using a 12 volt test light on
modern 'automotive' computer sensors is the best way to fry the PCM
known. It introduces 12 volts and a load to a low volt low load CMOS
system and will likely fry things.

I would almost suspect the OP was just out of gas....

Or that the new battery wasn't putting out enough volts to fire up the
PCM. The new Chrysler systems used are really bad for that.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's - Gone to the rust pile...
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)

philthy wrote:
> does the odometer say BUSS if it does you have a bad crank sensor and if the
> injectors are not firing thne you have a bad cranksensor and not a bad pcm
> pcm failure in jeeps is rear thing but get replaced because people (techs)don't
> know any better
>
> jtgreek wrote:
>
>> i have a 98 cherokee ,standard trans that won't start-cranks but has no spark-
>> no voltage with a test light
>> at the crank sensor harness,cam sensor harness,coil harness.i checked all
>> grounds that i know of
>> including the ground strap at the back of the head to the firewall-not frayed
>> at all.checked grounds by
>> pcm under hood,appear ok,checked grounds by coil.appear ok also.jeep was
>> starting fine-then i let it sit parked for 2 months-kids got in-left interior
>> light on-battery went dead-put in a different battery-cranks fine but won't
>> start-thought maybe some of gods little creatures got in there and chewed
>> wires-but didn't
>> see anything .i know i can't just try a different pcm from bone yard because
>> it has to be programmed
>> to the vehicle- anyone have any ideas -don't really have the money to take
>> to JEEP DEALER for
>> repairs.......oh and yes i did unplug and plug in crank sensor-didn't help.
>

Mike Romain

We were taught in electronics school that using a 12 volt test light on
modern 'automotive' computer sensors is the best way to fry the PCM
known. It introduces 12 volts and a load to a low volt low load CMOS
system and will likely fry things.

I would almost suspect the OP was just out of gas....

Or that the new battery wasn't putting out enough volts to fire up the
PCM. The new Chrysler systems used are really bad for that.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's - Gone to the rust pile...
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)

philthy wrote:
> does the odometer say BUSS if it does you have a bad crank sensor and if the
> injectors are not firing thne you have a bad cranksensor and not a bad pcm
> pcm failure in jeeps is rear thing but get replaced because people (techs)don't
> know any better
>
> jtgreek wrote:
>
>> i have a 98 cherokee ,standard trans that won't start-cranks but has no spark-
>> no voltage with a test light
>> at the crank sensor harness,cam sensor harness,coil harness.i checked all
>> grounds that i know of
>> including the ground strap at the back of the head to the firewall-not frayed
>> at all.checked grounds by
>> pcm under hood,appear ok,checked grounds by coil.appear ok also.jeep was
>> starting fine-then i let it sit parked for 2 months-kids got in-left interior
>> light on-battery went dead-put in a different battery-cranks fine but won't
>> start-thought maybe some of gods little creatures got in there and chewed
>> wires-but didn't
>> see anything .i know i can't just try a different pcm from bone yard because
>> it has to be programmed
>> to the vehicle- anyone have any ideas -don't really have the money to take
>> to JEEP DEALER for
>> repairs.......oh and yes i did unplug and plug in crank sensor-didn't help.
>

Mike Romain

We were taught in electronics school that using a 12 volt test light on
modern 'automotive' computer sensors is the best way to fry the PCM
known. It introduces 12 volts and a load to a low volt low load CMOS
system and will likely fry things.

I would almost suspect the OP was just out of gas....

Or that the new battery wasn't putting out enough volts to fire up the
PCM. The new Chrysler systems used are really bad for that.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's - Gone to the rust pile...
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)

philthy wrote:
> does the odometer say BUSS if it does you have a bad crank sensor and if the
> injectors are not firing thne you have a bad cranksensor and not a bad pcm
> pcm failure in jeeps is rear thing but get replaced because people (techs)don't
> know any better
>
> jtgreek wrote:
>
>> i have a 98 cherokee ,standard trans that won't start-cranks but has no spark-
>> no voltage with a test light
>> at the crank sensor harness,cam sensor harness,coil harness.i checked all
>> grounds that i know of
>> including the ground strap at the back of the head to the firewall-not frayed
>> at all.checked grounds by
>> pcm under hood,appear ok,checked grounds by coil.appear ok also.jeep was
>> starting fine-then i let it sit parked for 2 months-kids got in-left interior
>> light on-battery went dead-put in a different battery-cranks fine but won't
>> start-thought maybe some of gods little creatures got in there and chewed
>> wires-but didn't
>> see anything .i know i can't just try a different pcm from bone yard because
>> it has to be programmed
>> to the vehicle- anyone have any ideas -don't really have the money to take
>> to JEEP DEALER for
>> repairs.......oh and yes i did unplug and plug in crank sensor-didn't help.
>

Mike Romain

We were taught in electronics school that using a 12 volt test light on
modern 'automotive' computer sensors is the best way to fry the PCM
known. It introduces 12 volts and a load to a low volt low load CMOS
system and will likely fry things.

I would almost suspect the OP was just out of gas....

Or that the new battery wasn't putting out enough volts to fire up the
PCM. The new Chrysler systems used are really bad for that.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's - Gone to the rust pile...
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)

philthy wrote:
> does the odometer say BUSS if it does you have a bad crank sensor and if the
> injectors are not firing thne you have a bad cranksensor and not a bad pcm
> pcm failure in jeeps is rear thing but get replaced because people (techs)don't
> know any better
>
> jtgreek wrote:
>
>> i have a 98 cherokee ,standard trans that won't start-cranks but has no spark-
>> no voltage with a test light
>> at the crank sensor harness,cam sensor harness,coil harness.i checked all
>> grounds that i know of
>> including the ground strap at the back of the head to the firewall-not frayed
>> at all.checked grounds by
>> pcm under hood,appear ok,checked grounds by coil.appear ok also.jeep was
>> starting fine-then i let it sit parked for 2 months-kids got in-left interior
>> light on-battery went dead-put in a different battery-cranks fine but won't
>> start-thought maybe some of gods little creatures got in there and chewed
>> wires-but didn't
>> see anything .i know i can't just try a different pcm from bone yard because
>> it has to be programmed
>> to the vehicle- anyone have any ideas -don't really have the money to take
>> to JEEP DEALER for
>> repairs.......oh and yes i did unplug and plug in crank sensor-didn't help.
>