Ok so i was going to swap my 1989 Civic hatch DX cluster for a 90 or 91 Si cluster and when i examied the back of the cluster i noticed my DX cluster only has 2 plugs but the Si cluster has 3 plugs. Two of the plugs look similar to both the si and dx but the third plug on the Si is small and only has like four wires.. Now what is the purpose of the third plug. Any help would be sweet

 

Need some help

 

Bump for help please..

 

If I remember correctly the DX does not have a tach on the cluster. that plug is problably what runs the tach. don't quote me doh

 

that third plug is insignificant from what I've read. When I put a gsr cluster in my 91 si crx, it had one of the small plugs on it also, but everyone said not to mess with it. It is for things not used on the gsr cluster....no idea what it is for on the rex.

 

**** well im still clue less on what it does and if its even needed.. Someone fill me in

 

Bump

 

look around the site ive posted a link of the difference between the two it has pics and info on each wire and theres a pic of it some where too......so just look around?

 

Dude I've looked around and seen all those diagrams.. Obviously reading > you because i know how to wire a cluster up im asking about the third blue connector and what its purpose is

 

zzzzzzz. I just swapped a Si cluster into my DX. But as far as I knew, 89 DX can ONLY swap for a 89 Si because of this 3rd plug. And yes B16CRXT would be correct then, the 3rd plug does f*ck all. 89 DX to 89 Si is straight swap.
gl
-mello

 

So i can only swap to the 89 Si cluster becuse of the lack of the third blue plug correct?

 

meh try it anyway with the 91 cluster and see what happens. I've always done 89-89 swaps though because that's what I have learnt. Might as well try it, not like your car will blow up.
-mello

 

haha true true.. but if anyones selling a 89 si cluster with the two plugs let me know

 

it didnt effect anything on mine. I dont even have it plugged up on my gsr cluster, but it fits in the hole fine. Just go with it.