So long Renix, goodbye Bendix 9

I bought a complete 90 Laredo a few years back for $150 but never really did anything with it until I was compelled to get a title on it. I had built a nice rig out of one with a lien on it, and I was going to get a title on something, so this was it.

The initial idea was to build the truck with the bad title in this body, but when I found it needed freeze plugs, and thus I was pulling the engine, I ended up building a two door instead which was sitting useless with a 2.8 and no transmission. Rather than pull two 4.0s and find a home for both, I pulled one and put the 2.8 on the ground.

Good place for it.

So now I'm back to this one. In swapping in a regular booster/master cylinder, and getting rid of all the Bendix 9 parts I could get to, I realized it was integrated with the rest of the wiring harness as opposed to being added on the side. I couldn't just leave all that in there, so I figured on using another 90 Renix harness I happen to have in order to get rid of it entirely. Then I realized that for all that work, I could put a later model harness in it with newer manifolds, etc. Nothing wrong with Renix, just not my favorite.

For the price of a box of cigars, I picked up a 91 Laredo. The engine sounds terrible, but it's complete under the hood. It's a 4.0/AW4/231 with everything intact underneath, including a good front drive shaft. Sucks it has the D35 out back, but I already swapped a 92 8.25 under the 90 when I built the leaf springs. It has 5-6" of lift now, I'll probably tone it down to 4.5 before it's all said and done. It'll probably be towed behind the next project, a lifted 4x4 short bus turned RV, but that's another forum. I'll add pictures as the project progresses with good weather and time off.

Some people collect stamps, I build Jeeps on a shoestring.



First step from this point is removing the harness. I still have to pull the engine for freeze plugs, and I expect to build the AC system mostly from an 01 donor, so everything up front is already out. However, the donor doesn't have an overhead console and I want my compass and ambient temperature display, so I cut that circuit out of the original harness.



I followed the orange and black wire up to a splice wrapped in duct tape, where I cut it out.



The other side of the circuit follows the remainder of the harness through a hole in the firewall that the 90 doesn't have. When it's finished, I'll keep this circuit routed through this hole if I can manage it cleanly enough, but the engine harness is going to come mostly from the bulkhead connector in the end.



The other holes visible in that picture will be capped, as it's not going to need any of the cruise vacuum system or a speedometer cable when it's finished. The caps are easy enough to find with a good eye walking through a junkyard.

So here's where that part of the harness terminates, it's the Renix ECM.



I've established that the 91 doesn't have that hole in the firewall, and that so far to my knowledge, it's the only year in the first generation XJ that doesn't. I'll turn the grommet into a plug in case I ever feel like doing this again with a later harness.

Hadn't seen one of these in a while, it's the emission timer which turns on the maintenance required light to remind you to replace the O2 sensor at 80k miles. Most people unplug it and toss the module, this one remained.



Here's the plug for it, if you ever found it under your dash and wondered where it connected.



The fuse panel makes up the back side of the bulkhead connector, and after removing the center bolt from the outside half of it, it removes with two #3 phillips screws, one top, one bottom. You only have to make about six turns, and the screws will stay with the panel when you remove it. Fun fact: All years from 84-96 have the same hole dimensions and screw locations, so you can use any bulkhead connector in any year. That's not to say that one side will match the other as far as wiring goes.



This here is the headlight delay timer, which because I won't be using this harness, will remain mounted to the dash but gets unplugged for the swap. All first generation harnesses use the same timer.



Then I ran out of AA batteries, but I pulled the kick panels in each and established that the body harness connectors changed in 91. This is fine, because I recall that the Bendix 9 system has a large chunk of hardware mounted under the rear seat bottom, and it has to go. That space is too handy for things I might possibly (never) need to have when out running trails, and again, I don't want to leave a bunch of unneeded wiring where I don't have to. I'm pulling all the rear trim to install late smoke tinted glass, so what's a few more screws?

Here's the bulkhead mount in the firewall.



Here's the body connectors for the old style harness. To remove the pins, you pull the center retainer and it releases all of them at once.



Last time I changed a dash harness, I cut and soldered this wire for the power locks, but this time I decided to figure out the proper method of removal. Once the circuit breaker is removed, you can see a small tab next to the wire. Press the tab, pull the wire, and the breaker receptacle comes right out.



This is the delay wiper module, which is typical to the Saginaw steering column. That means you can use one from anything with a Saginaw column, be it Buick, Olds, Pontiac, Cadillac, Chevrolet, GMC, etc.



Should your delay go out and you can't find one right off, just remove it and plug the connectors together like this. This was the way they were configured for columns which weren't equipped with delay.



Here's a side view showing the wiring behind the fuse panel. The panel snaps to the bulkhead connector, in turn retaining it with screws into the firewall. You can see the pin retainers in either side of the connector, these pop out to release the pins.



Here's the backside of the bulkhead receptacle, complete with dog hair and trash from the carpet. Plenty of empty holes to add whatever.

Dash is out, Renix wiring is out and rolled up in a box.

Looks like the Bendix 9 wiring goes into the firewall on the passenger side through a large round hole, I'll get after that once the HVAC cabinet is out and the carpet is pulled back.