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'88 XJ 4.0L - Relay diagram/locations?

CRJeepin

NAXJA Forum User
Location
York, PA
Have searched, looked in the Haynes manual, looked under the hood, looked in the factory owner's manual and read a bunch of tech sites guys have put together, but can't find a diagram that shows what & where all the relays are on my 88 Limited.

Specifically, I'm trying to find out where the power antenna relay is.

So far, this is what I've pieced together - please add to the list and/or correct it!

1) Driver side fender, near ballast resistor - EGR relay (i replaced this with a fuel pump relay way back when, wondered why it had one more prong than the one that came out! Was incorrectly told it was the fuel pump relay. Now I can't find an "EGR relay" for sale anywhere, this must be called something else by the factory?).

2) Passenger side relay center (3 or 4 relays in a row): Second one back, fuel pump relay.

3) A/C relay?

4) Fog light relay?

5) Power antenna relay?

Thanks for any help filling in the blanks!
CR
 
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Calling the stealership parts guy won't cost you a dime.. A beer or lunch will go far!
 
CRJeepin said:
Have searched, looked in the Haynes manual, looked under the hood, looked in the factory owner's manual and read a bunch of tech sites guys have put together, but can't find a diagram that shows what & where all the relays are on my 88 Limited.

Specifically, I'm trying to find out where the power antenna relay is.

So far, this is what I've pieced together - please add to the list and/or correct it!

1) Driver side fender, near ballast resistor - EGR relay (i replaced this with a fuel pump relay way back when, wondered why it had one more prong than the one that came out! Was incorrectly told it was the fuel pump relay. Now I can't find an "EGR relay" for sale anywhere, this must be called something else by the factory?).

2) Passenger side relay center (3 or 4 relays in a row): Second one back, fuel pump relay.

3) A/C relay?

4) Fog light relay?

5) Power antenna relay?

Thanks for any help filling in the blanks!
CR

1.) No such thing as an EGR relay. There is a EGR solenoid that is right next to the ballast resistor, but it doesnt look anything like a relay. It has vacuum ports etc.

1.5.) The relay next to the EGR solenoid (described above) is for your electric fan. (only relay on the drivers side fender)

2.) Passenger side relay center (4 relays in a row)
Starting from the relay closest to the battery:

2.1.) A/C Clutch Relay

2.2.) +B Power latch relay (operates the IAC motor when engine is turned off)

2.3.) Fuel Pump relay

2.4.) Heated Oxygen Sensor relay

Here is a picture if you do not understand my descriptions:
2426393_11_full.gif


3.) The relay for factory fog lights is located on the top crossmember that covers the radiator. If your looking at the front of the engine, its on the right hand side near where the air box is / would be.

4.) The relay for the power antenna option is located below the passenger side panel below the glovebox. If you were sitting in the passenger seat, the panel is in the proximity of your knees.

Addition Important Information:

Replace all relays with SPDT relays (5 prong with 87 and 87a outputs) Not all the relay locations take a SPDT, BUT it makes it easier to diagnose problems when you can easily switch around relays. You cant do that if you just get 4 pin SPST relays (with only pin 87).

I hope that was informative and helps you.
 
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Muad'Dib said:

I hope that was informative and helps you.

Perfect, thanks a lot!!

I suspected there wasn't such a thing as an "EGR relay" (it didn't make sense electrically either) but that's what I'd heard it called a bunch of different places.

Will switch out the relays with SPDT's, thanks for confirming that it's OK to use the same relay for all of them. The relays are all factory original and look super crummy, and after all the work I've done on it I'd be pretty steamed if I got stranded because of a darn $5 relay!

Probably going to have to replace the power antenna, but will check the relay first, thanks. It sounds like the antenna is a fun one to get to :roflmao:

Thanks again!
CR
 
Muad'Dib said:
]3.) The relay for factory fog lights is located on the top crossmember that covers the radiator. If your looking at the front of the engine, its on the right hand side near where the air box is / would be/QUOTE]

That's a fan relay on my '90. Jumped it many a time with a fuzed pigtail to force the fan on full time. When the fan won't run, all I have to do is tap it with my finger and it kicks on - and a new one does the same thing. But that's a different story.
 
I looked in my 88 FSM and it matches the one from the Renix manual. The one earlier shows them all reversed. Maybe it was an error due to the viewing angle.
 
The diagram should apply to any Jeep 87-90.

The fuel pump relay is bypassed IIRC when starting.... as is the ballast resistor.. i could be wrong though.

The order of the relays are incorrect. Thats why one can apparently start the vehicle with the FP relay removed.

FSM for 1990 shows the opposite order. 87-90 are the same.
 
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