Adding low washer fluid warning to an MJ

[eaglescout526]

18 minutes ago, Minuit said:

Are there any markings on the cluster connector that could help identify it?

According to my 84, 85, 86 preliminary and 88 XJ electrical manuals, it is always pin 15 and on the connector itself it is numbered 1-16. But at C100 I can confirm that the electrical manual shows the sensor wire to plug in in different locations for each year except 84-85. 

[Anthi4078]

Ok so I’m back from the junkyard and I ended up just grabbing the column  and cruise control stuff. The a pillar trims did have screws going through them so I don’t think they are the rare ones. One thing I did find out about this Cherokee is that it had the mysterious Sentinel System. Unfortunately someone had taken the display but the computer box and all the sensors seemed to be there still.  P.S. the last photo is just to show what the blue box under the dash looked like. 

[eaglescout526]

Oooo and those are the rare pillars. The early ones don’t have a way to put the screw hole covers on unless someone swapped them. Did you grab the sentry stuff? I’d like to have back up parts for mine along with the computer. And the valve cover. 

[Anthi4078]

36 minutes ago, eaglescout526 said:

Oooo and those are the rare pillars. The early ones don’t have a way to put the screw hole covers on unless someone swapped them. Did you grab the sentry stuff? I’d like to have back up parts for mine along with the computer. And the valve cover. 

Oh yeah the screws just stuck out of the pillar. They don’t look like mine with the places for the covers. I didn’t grab any of the sentry stuff because I wasn’t sure what it was until I’d left and was looking it up. 

[eaglescout526]

16 minutes ago, Anthi4078 said:

Oh yeah the screws just stuck out of the pillar. They don’t look like mine with the places for the covers. I didn’t grab any of the sentry stuff because I wasn’t sure what it was until I’d left and was looking it up. 

I’d go back and grab it along with the on board shock air compressor in the corner on the passenger side by the firewall. 
 

Actually can you just get me that whole engine bay lol. Man that XJ is full of goodies. 

[Anthi4078]

1 minute ago, eaglescout526 said:

I’d go back and grab it along with the on board shock air compressor in the corner on the passenger side by the firewall. 

Oh that’s what that was. I was trying to figure out what the little switch was for. I didn’t know these jeeps had air shocks

[eaglescout526]

20 minutes ago, Anthi4078 said:

Oh that’s what that was. I was trying to figure out what the little switch was for. I didn’t know these jeeps had air shocks

It has everything tied to that? Oh my! I need such. Yes they came with air shocks in waggy limiteds and special order XJs. I have the shocks as NOS but need the compressor and everything tied to it. Shoot me a PM and we can discuss this without clogging this soon to be informative thread. 

[eaglescout526]

Ok so this isn’t going to be as easy for 87-90 as it would be for the 86’s. I should’ve known looking at the picture of the C100 was going to have different terminals and I put AMC logic into my head and thought why would they use anything different. Well they did and here’s the terminal style everyone else is going to need:

 

 

I am not sure of the terminal name that goes into C100 but it looks metri. 

[eaglescout526]

Ok hardest part is done which is unplugging the C100 and removing the cab side to gain access to the block to remove the retainer to slid the terminal in and putting it all back together. To verify I put it in the right spot I tested continuity from the engine side connector to the pin for slot 15 and I have continuity. Honestly, this mod is not for the feint of heart to do. It requires some hand acrobatics, a second person to push the C100 back together and some know how. If we want I can do a write up of setting an MJ up with the lamp using the info from this thread.   

[Ωhm]

33 minutes ago, eaglescout526 said:

To verify I put it in the right spot I tested continuity from the engine side connector to the pin for slot 15 and I have continuity

 

When you say 'engine side connector' are you referring to C168?

 

 

[eaglescout526]

22 minutes ago, Ωhm said:

When you say 'engine side connector' are you referring to C168?

Yes and right now I still don’t have the lamp illuminating. Working on it right now. Bulb is confirmed good. 

[eaglescout526]

Ok I’ve hit a point where I’m gonna keep going on this but this is not worth the effort. So the MJ harness is very specific at this point. To add the low washer you also need to give the plug power which it does not have and the power wire for the plug goes into the cab and is controlled by the radio fuse. So it’s switched and adding it directly to battery power is not advised here unless you want to end up with a dead battery. 

[Ωhm]

Does C100_C2 only have a wire on the IP side of C100?

[Ωhm]

One more check. Does C100_F6 only have a wire on the ENGINE side of C100?

[eaglescout526]

19 minutes ago, Ωhm said:

Does C100_C2 only have a wire on the IP side of C100?

 

17 minutes ago, Ωhm said:

One more check. Does C100_F6 only have a wire on the ENGINE side of C100?

So both wires are present on the engine side. They are not present on the cab side. They have to be added. Purple with orange tracer to radio fuse and white with black tracer to slot 15 on the info center plug. It’s not too bad of a job so long you have an XJ dash harness doing nothing with the two wires and a free 3-4 hours doing this. Granted it will be less now that I figured it all out. Would I do this again to another MJ? No. Would I do it if the MJ had no interior, sure! So long you have an XJ harness doing nothin. But it’s added and here’s proof of it working:

[Ωhm]

Yea, what I was wondering if you could have used FUSE Turn B/U (C100_C2 not used) for power to Low Fluid Warning SW.

[eaglescout526]

16 minutes ago, Ωhm said:

Yea, what I was wondering if you could have used FUSE Turn B/U (C100_C2 not used) for power to Low Fluid Warning SW.

You could and honestly the power wire can go anywhere so long as the power is a switched power source like the radio and lamp fuses. I guess my concern with the turn/BU lamp fuse is that the light would probably illuminate only at that time when either the signals are called for or the back up lamps. 

[Ωhm]

This would be power to the switch, not out of the switch, but you're up and running now.  

[eaglescout526]

9 minutes ago, Ωhm said:

This would be power to the switch, not out of the switch, but you're up and running now.  

Yes, you just don’t want it to be a constant 12v to the switch otherwise the light will be on till the battery dies. And yup! Now I just need a big enough circle saw to fit the sensor tightly into the washer bottle. 

[fiatslug87]

6 hours ago, eaglescout526 said:

If we want I can do a write up of setting an MJ up with the lamp using the info from this thread.   

YES please!!!

[Anthi4078]

I just measured the hole in my bottle for the sensor and it’s 1” 5/16 or about 34MM

[eaglescout526]

34 minutes ago, fiatslug87 said:

YES please!!!

Okie dokie. I’ll work on getting something written up. Honestly the life saving thing factor here was having the XJ harness of the same year range. 

[Airborne Janitor]

Confirmed this does work. I did simplify the process by not plugging into the C101 bulkhead connector. I just ran new wires to and from the low washer switch. I have a 97+ XJ washer bottle so my set up may look a little different.

 

 

Pin 15 missing from the instrument cluster info panel harness. Pulled an individual wire I had from a spare XJ harness and popped it right into the MJ harness. Its easy to remove the pin from the harness using an awl or a pick. Crimped a QD spade to the other end of the wire.

 

 

Spliced into the low washer switch. Ran two wires from it back into the cab through the firewall. Drilled a hole and popped in a grommet.

 

 

 

Run one wire to the Pin15 wire, and the other wire to the fuse block, splicing into the radio fuse, upper left. 

 

 

Testing the low washer light by activating the float for the low washer switch.

 

 

 

Here's a simple diagram to follow.