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New CPS install & questions

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I apologize in advance if this has been answered before. I tried using the search thing but it keeps telling me there are no results.


Anyways, today I was working on changing my CPS until I ran into a small problem (not enough socket extensions lol)


I have a few questions. They don't all have to do with the CPS, but I'm trying to avoid being the annoying new guy who starts way too many threads.


Question #1. Since I don't own a multimeter (it's on my list of things to buy, just haven't yet) is it fair to assume the cause of my crank no start is my CPS due to the fact that I can disconnect it and get the exact same problem as when it is connected?


I am getting no spark.

I can hear the fuel pump kick on so I don't believe it's a fuel issue.


Distubuter and cap look fine, plugs are fine, and ICM is newish.


I still need to drain and replace all fluids.


Question #2. I've noticed a few vacuum hoses are disconected, could any of them cause a crank no start? Is there a diagram for all the connections on the 86 2.5l?


Question #3. My MJ is missing a fan clutch, fan, and shroud. Is there a direct replacement available or what should I look for at the JY if they have no MJs or XJs.


Question #4. When I turn the key, my horn would blast. Was causing issue with neighbors so I had to disconnect the horn. What could cause this?


Question #5. The digital clock inside works, gauges on the cluster work (minus the fuel gauge), and I hear a buzzing when I turn the key. However I can't get the radio to work. It's a factory radio. If the wiring was bad, wouldn't the cluster and clock not work?


Thank you for any help. This is my first project of this size and I'm a little clueless

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I'm no expert on the Renix. Haven't messed with one yet.


#1. See above, but I wouldn't expect that unplugging something essential to your engine running and have it not run is a valid way to diagnose it as not working.


#2. Vacuum leaks can cause high idle and running like $#!& (if it's in the line for the map sensor) but I can't see them causing a no-start.


#3. The AMC 2.5l also went into '90's Dakotas, but I can't guarantee it's the same. A lot of 2.5 and 4.0 parts are the same, but I don't know about those ones.


#4. The horn button works by effectively shorting the wire against the steering column. There could be a problem with the multi-function (i.e turn signal) switch or it's wires which is where the horn button gets power. Likely it's rubbing on the rod which actuates the ignition switch. The ignition switch itself is at the base of the column, so I doubt the problem is with the wiring between the two. Just to be clear, the horn was only sounding while the key was briefly in the start position?


#5. The radio wiring is separate from the gauges, although there are a couple other things on the circuit, cigar lighter and blower motor maybe? Can't remember and don't have the wiring manual with me. There should be a fuse in the panel marked "radio". Check it. Can't say how or why, but it was blown in both my MJ and parts XJ when I got them. It fixed the radio in both. Hasn't blown in four years in the MJ, the XJ's dash and fuse panel are now sitting in my basement.


Hope some of that helps. I'm mostly responding cause no one else has yet.

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