Hello!
I’m here hoping to find some advice to help me help my dad with an issue we have with his 1999 Jeep Cherokee XJ’s PDC connections.


Diagnostic:
Off and on, over the last couple months we’ve chased a intermittent issue with his fuel delivery system. Finally we narrowed it down and found that the system is working as intended, but the intermittency is being caused by a loose connection to the Fuel Pump Relay in the under hood PDC due to broken retaining tabs that should’ve been holding the wires.

We found that the cause of the broken tabs was likely caused by rough handling of installing/removing the relay. Once the tabs retaining the wires break, the relay would simply push the wires down instead of locking into place.


Location/Install:
The “relay block” installs from the bottom of the PDC and is underneath the yellow frame. If more information on location is needed please let me know.


Replacement Parts:
I’ve looked all over online, searching the three different number/ letter combinations on the bottom side of this “relay block.” (For lack of knowing it’s name.) The only thing that I’ve been able to dig up is a Chinese website referencing one of the searches, and the other two number/ letter searches didn’t pull up anything relatable.


Considerations:
We attempted to salvage a “relay block” from a another PDC, but the plastic is too old and brittle even with heat or lube to remove completely. There would be the option of splicing in a new PDC with all the wires still intact, but an awesome thing would be to find a new “relay block” without broken tabs. I’ve exhausted the local resources I have, and there’s few other options we’ve considered but nothing as good as a standard replacement.


I’m not sure if this has been a common issue at all or I at least didn’t see another form directly addressing this, but if I missed it I apologize and I appreciate you’re help and advice!

Thanks,

Skyler

 

Welcome to the forum.

Yes its not uncommon; I think over the years of heat cycles, its amongst the most brittle plastic that's in your engine bay. I broke many a clip and have looked for replacement too. Def as a result from removing/installing relays. It took really nothing to break. Junkyard ones will have the same issue and not sure if you can source a new replacement.

I ended up leaving that yellow part/relay 'crate' out, securing the tabs from underneath and pushing the relay in. You can glue them in place too, make sure you verify the correct slot!

 

I had something similar happen with mine. Except I had a wire terminal that would not stay "clicked" in. If you inserted the relay, it would just push the terminal out the bottom.

JB Weld came to the rescue for me. I JB Welded the terminal in and it works fine. I don't plan on getting into the PDC anymore so hopefully I am good to go.

 

Thank you!

Yes, both of those situations apply! Funny enough my dad had the same idea to leave that yellow tray out as well, and we held the relay in the block while pushing the wires in place for a temporary fix. Everything is working great until the next time the relay needs removed, then we'll have to pull the Power Distribution Center back off the bracket. We looked at replacement PDCs, but only found used OEM and junkyard ones. If new PDCs, or new relay blocks were made then this repair would be very easy. I've search to see if there are new parts out there a few times and have come up with nothing of real use. I also thought about the possibility of 3D printing a new relay block, but I'm not sure how complicated that could be.

The best idea me and my dad had appears to have been thought of as well, gluing the wires in place. The only issue that we've thought of with gluing the wires in place is that there are very likely future repairs on the PDC and retaining the integrity and length of the wires we've concluded is the preferred outcome. So we kept thinking.. Trying to salvage an intact relay block would be good yet it is not feasible, we attempted this and if even one of the 8 tabs break you're right back where you started. Next, replacing the PDC seemed good until we thought it out, the issue with a used and intact PDC would be splicing all the wires in place, since you wouldn't want to remove the wires from the relay block and break tabs.

All in all gluing would defiantly be our preferred method of fixing this connection given the absence of new replacements, but I'm hoping we found something else that'll work too.

So far we've not been in a rush, and over the last week we started looking at relay sockets. This idea started with a few single relay sockets that my dad had left over from his switched electric fan mod. We thought we might be able to use two of these relay sockets to replace the relay block. Then I stumbled upon a double relay socket that resembles the OEM relay block, kind of.
*(I'll attach a photo)
Summit Racing sells a 30Amp Dual Relay Socket with relays, and I found another website selling a 40Amp Dual Relay Socket without relays. We haven't gotten the relay sockets delivered yet, but I just wanted to share the progress so far and thank you guys for the support and suggestions!

Attaching these sockets may end up a little crude, but I'll be sure to follow up so hopefully if other people do this as well it'll be improved. Or avoided if it goes bad..
Our plan is to remove the wires that come with the sockets, and with new connectors on the OEM wires slide them in place. Then the creative part is going to be finding a good way to secure this dual socket in the PDCs housing.



**Double Relay Socket ^



Thanks!

 

Seems like something a friend with a 3d printer could solve for you. I don't have one or access to one so just th inking out loud

 

there is a member @boxburn that 3D prints XJ parts