Thread: Simplifying the Chassis Harness - Is it really needed?

I'm looking to simplify the chassis harness while the car is completely apart and I have the harness out of the car. Simplifying means, taking out the crap I am not going to use anymore, i.e. AC, windshield washer. I just need the basic essentials, i.e. lights, fans, etc.

Below I have attached the FSM chassis & motor wiring diagram & legend as a reference. I condensed everything into one sheet.

The plan is to de-loom the chassis harness and pull out the plugs that are not needed anymore. So far I have identified the following as not being needed:
Washer Fluid Level Switch (E32)
Front Washer Motor (E33)
ABS Relay Box (E36)
Air Conditioning Relay (E42)
Dual Pressure Switch (E12) - Is that the plug for the canister attached to the AC condenser?

FYI - I will be using a standalone (which really only applies to the engine harness).

Which other wires/plugs are really not needed for what I want to do? Any suggestions and recommendations are appreciated.

What is "ASCD?"

automatic speed control device IIRC... cruise control

I figured. I just couldn't make out the acronym

I actually cut the most of my chassis harness out down to the rad fan since my ems turns on the fan. I actually deleted the the fuse box

I can't quite do that. I need functional lights, etc. I just need and want the basic essentials.

I kept my lights and all. What I did was open the harness that runs from the driver side to the passenger side and then started removing all the unnecessary AC, Fog Lights ETC. Once those were unraveled from the harness all I was left with was the Alternator and headlights/signals. Then I back tracked that and removed the wiring all the back prior the fuse box.

I take it that this is for a b14, correct?

my car is bare bones, just head lights tail lights indicators and horn and fan. i start from the fuse box and rip out the wires to the relays i dont need as well as the fuses i dont need. i also cut out all the grounds. i then rip all those wires out until i get to the smj. under the dash, and de pin them. once shes cut down to shape, i use the service manual and trace all the wires i do need. and lay them nicely in the frame, then i cut them down to length where needed and add wire where needed. then i reground everything nice and neat. if i am using hids or anything of the sort i like to mount the ballasts permanently then do the wiring this makes the wiring much easier when all your devices are mounted.

this method works for the engine bay harness as well as the under dash harness. , when u take the harness out the car its easiest to plug in everything (head light bulbs) dimmers switch hvac controls ect ect) this way you know what plug is what, easier, tape and label, and start wacking out the unneccessary shit.

i will be honest i almost feel its easier to rewire from scratch, but it would cost more money, but it would be a better job

What did you guys do with the fusible link & fuse box that is on the driver side? What is the "engine cont" fuse? Could never really figure what that is...

I doubt I'll mess with the under dash harness.... that is a complete cluster fuck. The electrical FSM is a nightmare.


Yes.