Dangling Mystery Connectors - What Are These For?

E28 technical advice asked and given! Troubleshooting, modifications and more.
Post Reply
laszlo
Posts: 24
Joined: Jul 28, 2022 10:16 PM
Location: Montreal, Canada

Dangling Mystery Connectors - What Are These For?

Post by laszlo »

Hi there. Recently bought an '86 535i with the stock M30B34. It runs a little rich and the idle is rough. There seem to be a bunch of connectors dangling around my engine bay. Can anyone help identify these? Is my wiring harness completely screwed?

#1 Small black connector, near charcoal canister. Brown & blue/brown wires.
https://imgur.com/a/3hXjFY6

#2 Large black connector, near charcoal canister. AMP 926 172. Brown & yellow/brown wires.
https://imgur.com/a/MyFcsiX

#3 Cut Wires, passenger side. Black and brown wires.
https://imgur.com/a/BDiRSLW

#4 Two single connectors, near fuse box. Brown and green/brown wires.
https://imgur.com/a/qXZJagW

#5 Narrow yellow connector, near power steering reservoir. AMP 926 589. Purple & yellow/purple wires.
https://imgur.com/a/Y6QqJSf

#6 Black connector, above brake fluid reservoir. Green/brown & green/white wires.
https://imgur.com/a/UYQU5eu

#7 Dangling mini connectors, near brake master cylinder.
https://imgur.com/a/3iNsaM4
Blue Shadow
Posts: 10195
Joined: Feb 12, 2006 12:00 PM
Location: SE PA

Re: Dangling Mystery Connectors - What Are These For?

Post by Blue Shadow »

1-washer fluid power or level, see ETM to determine which
2-fog light
6-heater control valve
7-power flow regulator switches

get the etm for your car from www.e38.org/e28 middle of the left column in the Electronics section and check the wiring colors for those and more.
laszlo
Posts: 24
Joined: Jul 28, 2022 10:16 PM
Location: Montreal, Canada

Re: Dangling Mystery Connectors - What Are These For?

Post by laszlo »

Blue Shadow wrote: Aug 14, 2022 12:43 PM 1-washer fluid power or level, see ETM to determine which
2-fog light
6-heater control valve
7-power flow regulator switches

get the etm for your car from www.e38.org/e28 middle of the left column in the Electronics section and check the wiring colors for those and more.
Thank you for the info! With all of these unplugged connectors, do you reckon I'm missing parts in the engine bay?
There's no accessory belt on the AC compressor pulley. The previous owner said the car had no heating.

I found this empty bracket https://imgur.com/a/2UpDR0Q - What normally bolts onto this?
Also, the wiring for the wiper fluid is really sketchy https://imgur.com/a/YQKBDm5 - This can't be stock? The windshield wipers & sprayers work.
Blue Shadow
Posts: 10195
Joined: Feb 12, 2006 12:00 PM
Location: SE PA

Re: Dangling Mystery Connectors - What Are These For?

Post by Blue Shadow »

bracket holds the heater control valve.
laszlo
Posts: 24
Joined: Jul 28, 2022 10:16 PM
Location: Montreal, Canada

Re: Dangling Mystery Connectors - What Are These For?

Post by laszlo »

Blue Shadow wrote: Aug 14, 2022 2:39 PM bracket holds the heater control valve.
Ok, so not essential for the engine driveability. Don't need heat, I'll tackle that later.
What function do the power flow regulator switches serve?
Ordnator
Posts: 550
Joined: Aug 31, 2015 7:34 PM
Location: Halifax NS

Re: Dangling Mystery Connectors - What Are These For?

Post by Ordnator »

You may have heated windscreen washer nozzles.

They take power from the screen wash motor on the screen wash reservoir.

Best regards,

Mick
Blue Shadow
Posts: 10195
Joined: Feb 12, 2006 12:00 PM
Location: SE PA

Re: Dangling Mystery Connectors - What Are These For?

Post by Blue Shadow »

PFR switches will light the Brake light below the tach, along with low brake fluid (three triggers). Low pressure in the PFR means power steering and power brakes in the 535 are compromised.
Post Reply