I have a 1997 XJ Sport that has multiple electrical problems. The current issue I have seems to be a parasitic drain. The horn started blowing by itself one day. Mechanic had it 6 months and finally just bypassed the horn and put a damn button on the dash. Since I got it back, the battery drained within a day. My wife wants me to totally rewire it. I don't really know what I'm about to get into. Are there wiring harnesses still available or am I going to have to cut and splice new wiring? Typically, how much would it cost to have someone else do it?

Also, it seems like I have a hole somewhere in the gas tank. I cannot find a 1997 tank. Will a newer one (1998+) fit properly?

 

A self-blowing horn....I'm going to let that one go passed.

I had self-igniting floodlights at some stage, which was a tad unhandy at night I can attest.

Before listening to the wife: have you considered checking for parasitic drain yourself? There are many youtubes on this.
I may hope your mechanic having had it for 6 months(!?) would have done that at least

If you found the drain, we can then look what circuits etc are involved.

 

The horns have a permanent live feed, so if the wire from the hornpush is damaged & goes to ground, it's like pressing the centre of the wheel. One of mine has a switch on the dash but that's 'cos I wasn't prepared to pay for a new clockspring & it was an excuse to upgrade the wiring & put a relay in the right place, i.e. between the battery & the horns (now both on the right).

Having a vehicle professionally re-wired would be very expensive, difficult to justify for an XJ (even at today's ridiculously inflated values) & may not fix a parasitic drain issue.

Personally, I found trying to find the cause of a parasitic drain to be more trouble than it was worth (although that was on a '96 Caddy, so a little more complex than an XJ) & opted for disconnecting the battery if I was going to leave it for more than 3 hours. You may have more patience than I but it's a quickfix to make the vehicle usable while finding the problem.

 

X2 for troubleshooting the parasitic drain. Troubleshooting and even learning what to troubleshoot is going to be easier than the rewire job your imposing. There aren't replacement wiring kits. There is the you wrench yard and your commitment to pulling an entire harness uncomfortably in a junkyard. While it's plenty cheap from all my experiences it's also very labor intensive. Engine bay harness is not terrible to remove - the interior under dash harness will involve a near complete gut job of the front of your jeep interior.

Unless you've got more $$ than time sure you could pay a different mechanic than your prior stud to do the work of troubleshooting.

 

Imagine spending all that time/$'s & still having the problem - 'cos the fault wasn't in the wiring at all, but a component.

I grew up never replacing anything unless (a) I knew it was the cause of the problem, (b) it couldn't be repaired; stood me in good stead all my life.

 

We, and our Jeeps, will get to a point that the repair or fix isn't worth the time or money......it is called obsolescence.

 

OK. I found a Jeep service Manual and I'm looking through it. I am pretty sure the relays aren't the source of the drain. Could a faulty clockspring be the drain problem? I ASSUMED the mechanics checked the relays and clockspring because they had it for so long, but I'm starting to second guess them. Also, the horn switch is part of the airbag system? I haven't torn into the Jeep yet because I don't have the place to store the parts, except inside the Jeep, and I don't want to lose anything...yet.

This post also helped me think about the problem: https://www.cherokeeforum.com/f2/horn-issue-200972/

 

downloading the free FSM is the only way to go

You are in USA ?, and from asking before, it seems you do not have auto electricians as a separate trade, which surprises me,

Over here, while some mechanics are handy fixing minor electrical issues, for specialist electrical work, that will usually be done by a auto electrician, and they can fault find pretty quick

Good chance yours got left to sit, when it wasnt obvious...till you took it away

I dont know how good you are at electrical. Youtube is your friend

start by disconnecting battery and seeing if it will light a test light, measuring the drain current with a multimeter may or may not be needed.

If it lights the test light, pull each fuse in the PDC, one at a time till you find the culprit. (If nothing lights, it may be unfused, but we will ignore that for the moment)

Once you have ID the main circuit, consult the FSM, and check the suspect circuit fuses under the dash

That should narrow down to just a few components

report back if more info is needed

any drain over about 30mA is too high

re wiring would be not economical (even if it was successful). Learning to repair electrical faults becomes important as the vehicles age

 

You make it sound so simple, & I suppose it is - in theory. "pull each fuse in the PDC, one at a time till you find the culprit" is all very well but, as I suggested earlier, maybe OP has more patience than me, especially when it comes to the fuse board behind the kickpanel

 

There is no quicker way.

Its the death of many vehicles

here is a free tip for the XJ

use a mirror and strong light shining up, a test light and fuse pulling tool or long nose pliers.

take some digipics and vid

You can test that whole underdash fuse board for blown or parasitic fuses in 10-20 minutes

Only at that time does one need to consult the FSM

Imagine an XJ goes to the scrapper cause of a single dud part

That is how my mate, who is a qualified mechanic and auto electrician acquired one (and many other vehicles). He would get them back on the road in no time and on sell them

 

Maybe not a quicker way but there is an alternative: unless it's an inspection fail, just leave it.

You've obviously never done the job on a RHD model - with the pedals where your head needs to be, & that damn door open chime right by your ear (even if you could actually get the kickpanel off in that short a time)

 

I dont think a parasitic draw should be ignored, as it is to risky and problematic, as it may leave you stranded, and/or roger your battery

lol..all my XJ are RHD...one reason I am so quick, one of my fuses pops every now and again, I think it is F9 under the dash, cant remember what I lose, power windows I think

Of course my door open chime is disabled, as I would rather it spat in my face than be chimed at

Get down on your knees.

Prayer style, on the ground, facing forward, with the light shining up,, and mirror, you can touch the tip of the test light on both ends of every single fuse tip in 10mins

The fuses are numbered, use a towel under your knees and across the door jam

@ the OP, you just leave the test light connected between battery main cable..it should go out when you pull one of the big fuses in the engine bay...how easy is that ?

then move on to the next step

 

I did a partial rewire of a 1970 era “step van” that will be turned into a food truck. It was days and days of work and hundreds of dollars. The only reason I rewire sit was cause it was a fire hazard and there had been multiple major jobs done to the electrical by people who were total hacks. Just find the problem. Or go one system at a time.

 

Can i ask a question?

 

yup


Wow, how did I not use this opportunity for a dad joke. The reply should be:

You just did.