computer and dif Q's

ok i have a 1988 xj with a 4.0 HO but i stop dead i have no power to the key at all but i can still turn my headlights on and i have brake lights what could it be and i got a 88 waggoner same 4.0 auto will it have the same computer in a 5 spd
my other Q is the spider gears in the front dif where taken out how hard is it to put back in???

I think your ignition switch is broken/fried. Also, are you going to try and switch computers? RENIX era (87-90) computers basically never die, ever.

But I think the computer is the exact same, yup.

Wtf? You can't use a renix computer with 91+. Timing changed, along with a plethora of other stuff. Not to mention 91+ became chrysler and it had a CEL light.

And up until 96-97? the transmission is controlled seperately from the ECM-it uses the TCM.

I think the OP was a little confused and does NOT have a H.O. engine. He has a renix era engine and thus you may be right about his ignition switch being fried.
Big it is not at the key as everyone mistakenly thinks. It is in a box on top of your steering column but below the dash covering. A little hard to visualize without contorting yourself into a weird position. You pull off the lower dash covering and remove the two bolts that hold the column up and it will drop down. There is a rod from the stering wheel end that extends from the lock (key) to the box which contains the actual switch. It is a plug 'n play operation from there and then just reverse everything you removed and you should be good to go.
Hope that helped you out
Blue

90Blue_XJ said:

I think the OP was a little confused and does NOT have a H.O. engine. He has a renix era engine and thus you may be right about his ignition switch being fried.
Big it is not at the key as everyone mistakenly thinks. It is in a box on top of your steering column but below the dash covering. A little hard to visualize without contorting yourself into a weird position.

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it dose have a 4.0 H.O. it was put in , and yes i no that the power does not go to the key its self and i changed the swich already so what eles could it be???

Oh, I missed the HO part. In that case, the computers won't be interchangeable.

Not sure 'bout your wiring though.

the_big_o said:

it dose have a 4.0 H.O. it was put in , and yes i no that the power does not go to the key its self and i changed the swich already so what eles could it be???

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OK you have a HO long block(or possibly short block and RENIX head) but it is controlled by the RENIX system
(unless the whole Jeep has been re-wired to the OBD1 system).

Correct? We need to know to help you with your question.

Follow the wires coming off the battery-they likely go somewhere. Are they connected to anything?

So, did it start after you changed it or is this just a problem that occured recently?

You are aware that the sensors/harness between 87-90 to 91-96 aren't interchangable?

89CherokeePioneer said:

Follow the wires coming off the battery-they likely go somewhere. Are they connected to anything?

So, did it start after you changed it or is this just a problem that occured recently?

You are aware that the sensors/harness between 87-90 to 91-96 aren't interchangable?

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ok lets start over the truck was running in my yard and then it died tied to start it didnt so i left it over night
next day looked on line for common problems seen ign. swicth so changed it still nothin now i dont no what it could be
P.S. i didnt make the truck it was given to me and he said it had a 4.0 HO so i dont no lol

Ok.. Look near the battery. You should see the starter relay with an assload of connections to it. The positive battery cable branches off here. This is where you'd get power. Is it connected, is it tight? How about the fusible links? They should feel solid, not like boiled spaghetti.

it was cold when i checked the links befor il check em agen and i tryed the relay but didnt do anything

Ok, if you have that relay, then it's still atleast in part Renix. 91+ got rid of that and had some power distribution block or something odd in its place.

Are you certain the batterys okay? Connections alright?