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92 jeep cherokee charging system

i just bought a 92 jeep cherokee larodeo 4.0 from this older lady she told me they had recently had the

alternater replaced and the batter needs replacing…well i drove the jeep hom or atleast attempted to

i made it only 7-8 miles before “alternator like symptoms” happened well i emoved the alternator and had

it tested at oreilly …they said it passed …i reinstalled the alternator and did a

visual inspection of the wiresto and from the alternator all appers well…on the outside…i took a

battery from a pontiac sunbird an put it in the jeep just to get it has far has i could and i actully

made it all the way home…which is around 20-30 miles i did a amp test on the battery before shuttin

down the truck with no accessorys running i was getting 11.5 with heater 11.4 and radio and heater 11.3

amps i went to dissconect battery wire while the jeep was running an it lost all power (it should have

ran off alternator alone…if alternator wworks properly) i am at a stand still here i dont know where

o really go next if i knew what to test and what to expect for results and what to look for i may be able

to get it …please offer any advice you may…also i dont know if the voltage regulator is an internal

or an external …i heard it may be intergrated into the pcm…but unsure…also i checked all fuses…

visualy…and those apper intact has well thank you for your time

The PCM may very well be part of the system as Chrysler uses that design a lot. There may be a bad wire connection causing the trouble and hopefully that is all it is. You would be wise to invest in a service manual for the car. I recommend a factory manual since they are the best and provide the most detail. You can get them off Ebay for a good price. It will be one of the best investments you can make on the car.

There usually is a fuse or fuseable link between the alternator output and the battery. If this is open the alternator will be putting out the correct voltage but the battery will not be charged. The 11.5, 11.4 and 11.3 amp? numbers sound more like voltage measurements. If so the battery is being run down by the load and the alternator is not charging.

I assume that the alternator warning dash light or battery light is not lite. Measure the voltage on the output terminal of the alternator. If it is around 13.5 to 14.0 volts using an analog meter but the battery is still at 11.5 volts, you do have an open between the alternator output lug and the battery terminal. A digital DVM will read oddly due to the A/C voltage on an unloaded alternator output.

Get back to us with more details and we can help more.

sorry i ment volts…so far i have replaced the wire harness from alternator to battery an all thats on that harness replaced alt fuses which didnt need it but whats it hurt right?and i just put a new alternator in agian…and still system not charging…tommorow im going to go pull a ecm out of a jusk year …compair all numbers first of course…my other issue is i have no idea where the voltage regulator is…any help is much appreciated…oh also i pulled a code 41 on it…but that doesnt come up till the battery is almost dead