Update! My wiring nightmare... where do I go with it?

[Rob Zaeos]

Back story:

1971 2002 6 fuse

This car is new to me, and came with a few issues that need sorting. I've been going through some mechanical and fit & finish issues, but the part that is more of a mess than i anticipated is the wiring, which isn't my strong suit.  It all started with the blinkers not working. I changed the flasher unit and they started working again, however when I put on the left signal the dash lights also came on, when i turned on the right signal the rear right running light also came on.

 

Went for a drive and all the sudden i heard the electronic fuel pump cut out. Blinkers no longer worked and had to pull over. Turns out every time I hit the brakes it blew the circuit breaker someone installed, and after a minute it would reset. Got home and stated looking for the issue. Chased a bunch of bad grounds and fixed them. The brakes no longer trip the breaker but the blinker issue persists.

 

I started looking further under the dash and there is trouble, a LOT of trouble.  The PO installed an alarm and stereo along with electric fan, e fuel pump, and edis... all while using the same wire colors for various sections.  There are also bunches of wires simply melted together. It's a F'n mess.

 

If been pulling wires apart, checking continuity and taping them up, staring at wiring diagrams, watching videos and reading posts but the blinker problem persists.

I don't care about the alarm or stereo... So going to strip them out for now.

 

So, wondering where do I go from here? should i even bother? Should i just get a painless system or a old loom? Am I even capable of that much commitment?

 

Also considering paying someone else to do it but really have no idea what that would cost, or who would be able and willing do deal with it. Any advice would be welcome and, new to LA so any suggestions on 2002 experts in the area would be appreciated.

 

Thanks in advance!

Edited October 14, 2023 by Rob Zaeos

[Mike Self]

Oh my...you really have a mess under that dash. My sincere sympathies.  somewhere on the FAQ there should be a wiring diagram for a six fuse US spec 2002, or you can buy a large, full color one from Prosperos Garage (prospero@colorwiringdiagrams.com).  Then with diagram in hand, start tracing circuits one at a time.   

A couple of tricks to remember when working with factory 2002 wiring:

• Solid color wires are hot all the time
• wires with tracers (two colors) are only hot when the ignition is one
• solid brown wires are grounds.

 I'd try to remove as much of the PO-added wiring as you can before doing any circuit tracing.  Start with the wonkiest one, which sounds like your turn signals.  Both the emergency flashers and turn signals are wired through the flasher relay, and the current for the turn signals flows through the emergency flasher switch--that red knob atop the dash to the left of the instrument binnacle.  

 

And...the turn signal lever has a couple of extra terminals that aren't used on US 6 fuse cars; if wired up, they allow the left or right parking and tail lights to be illuminated by selecting a left or right turn with the stalk, with the ignition off.  It's possible that a PO connected one of the turn signal wires to that terminal, and somehow inadvertently wired a tail light into the turn signal circuit.  Or there are crossed wires (or a bad ground) back at the tail lights.  The possibilities are (unfortunately) endless.  

 

Keep us posted as you find things, and take pictures of wiring hookups at switches, lights etc to help us help you.  By the time you have things right, you're gonna be an automotive wiring expert--at least on 2002s!  And be thankful it's a '71, not a '21!

 

mike

[Rob Zaeos]

13 minutes ago, Mike Self said:

Oh my...you really have a mess under that dash. My sincere sympathies.  somewhere on the FAQ there should be a wiring diagram for a six fuse US spec 2002, or you can buy a large, full color one from Prosperos Garage (prospero@colorwiringdiagrams.com).  Then with diagram in hand, start tracing circuits one at a time.   

A couple of tricks to remember when working with factory 2002 wiring:

• Solid color wires are hot all the time
• wires with tracers (two colors) are only hot when the ignition is one
• solid brown wires are grounds.

 I'd try to remove as much of the PO-added wiring as you can before doing any circuit tracing.  Start with the wonkiest one, which sounds like your turn signals.  Both the emergency flashers and turn signals are wired through the flasher relay, and the current for the turn signals flows through the emergency flasher switch--that red knob atop the dash to the left of the instrument binnacle.  

 

And...the turn signal lever has a couple of extra terminals that aren't used on US 6 fuse cars; if wired up, they allow the left or right parking and tail lights to be illuminated by selecting a left or right turn with the stalk, with the ignition off.  It's possible that a PO connected one of the turn signal wires to that terminal, and somehow inadvertently wired a tail light into the turn signal circuit.  Or there are crossed wires (or a bad ground) back at the tail lights.  The possibilities are (unfortunately) endless.  

 

Keep us posted as you find things, and take pictures of wiring hookups at switches, lights etc to help us help you.  By the time you have things right, you're gonna be an automotive wiring expert--at least on 2002s!  And be thankful it's a '71, not a '21!

 

mike

This is so helpful already! I had no idea about the solid vs. striped wiring, and great advice about how to approach it.

And also didn't know about the current flowing through the hazard.

This forum is always so great!!

I'll take pics and post more of the progress as I go.

Thank you!!

-Rob

 

[0257]

My friend Dave Wetzel makes full and partial wiring harnesses for ‘02s.  He could help you figure out which parts of the harness would benefit from a complete re-do, and work from there. Clean work, not exhorbitantly expensive.  PM me if you want to follow up with Dave.

[AustrianVespaGuy]

Yeah as bad as it looks, this is totally fixable.  As Mike indicated, you want to tear out all the 'new' stuff and leave the original stuff alone.  Fortunately, it seems like it's pretty easy to tell the two apart! Once you have all that 'aftermarket' crap ripped out, things will get MUCH easier, and we'll quickly be able to trace any faults left with the original wiring/systems. Granted that Megajolt is probably running your ignition at the moment, so we might need to keep that, but I still say the first step is to get all that crappy wiring out and then rewire it PROPERLY if you going keep it.

[halboyles]

8 hours ago, Mike Self said:

Solid color wires are hot all the time

Just a slight clarification to Mike's pointers.  Solid Red wires are hot all the time.  But the solid green wires are hot only with the ignition key in the start/run position.  The positive green coil wire being a good example.

[Tdh]

Man I hate seeing things like this.  You're lucky you didn't start a big fire!  Get this fixed before you drive the car again.  I know it sucks, but trust me.  A car fire gets out of control fast...astoundingly fast.  

 

You can do this.  The electrical on these cars is very simple and straight forward.  I agree completely with @Mike Self and @AustrianVespaGuy.  Don't bother trying to "fix" someone else's shitty work.  If you already have fried wires, then you probably have some compromised terminals or insulation in places that may not be so obvious.  If it were me, I'd remove/rewire everything he did. 

 

You listed a few things your PO did (fuel pump, mega jolt box for EDIS, alarm, stereo, fuel pump).  Re-wire all of that.  When I add things like that to a car, I generally do so using a separate fuse block (like this https://www.bluesea.com/products/5028/ST_Blade_Fuse_Block_-_6_Circuits_with_Cover)  so I can isolate the non-stock circuits from the stock harness.  

 

A painless harness is an option.  It won't be stock, and might hurt the value of the car a bit from a resale standpoint.  However, if done right it'll be a great upgrade from a usability standpoint.  Painless likes to build their harnesses with truly separate circuits from the fuse box out (no shared grounds).  This makes it easy down the road to diagnose trouble.  The trade off is that it'll be more work to install than the stock harness.  Attached are a few photos of an old Land Rover I rewired for a guy using a Painless off road harness so you can see what I mean.  The photos aren't from the final finished product, but its pretty close.  For comparisons sake, google a photo of a series land rover engine bay with stock wiring.  It'll look different for sure. 

 

Whichever route you go, be diligent about fastening/routing wiring in a way that keeps if from moving around and rubbing.  Learn from your PO's mistakes! Again, you can do this.  Take it one circuit at a time.  Once you get through a few it'll start to go faster.  

 

 

 

Edited October 14, 2021 by Tdh

[Oldtimerfahrer]

@tdh those are land rover pictures and you can get an entire new harness for series land rover's for peanuts...really peanuts, but noone seems to sell an affordable 6 fuse harness for 2002s for reasonable money.

A.

[Tdh]

Just now, Oldtimerfahrer said:

@tdh those are land rover pictures and you can get an entire new harness for series land rover's for peanuts...really peanuts, but noone seems to sell an affordable 6 fuse harness for 2002s for reasonable money.

A.

Totally agree.  That harness plus what the owner paid me to install it cost over 10 times what I would have charged him for an original harness plus install.   The story on that truck is that the owner wanted (in his opinion) better than original electricals.  What he ended up with is arguably better, but its also more complicated to understand for a novice to get their head around.  

 

Sorry if attaching the Rover photos bugged you, but I did it to give the OP an idea of how different a Painless harness would look/be to put in.  Also, to give him an idea of what a "decent" wiring job is supposed to look like.  

 

 

[Oldtimerfahrer]

Hi, no criticism, just that on rovers you have cheap alternatives....

A.

[Mike Self]

6 hours ago, halboyles said:

ust a slight clarification to Mike's pointers.  Solid Red wires are hot all the time.  But the solid green wires are hot only with the ignition key in the start/run position.  The positive green coil wire being a good example.

Damg!  Learn something new every day...

[irdave]

15 hours ago, All Day said:

... but the part that is more of a mess than i anticipated is the wiring, which isn't my strong suit...

 

That's about to change.

 

As everyone has said, you can do this.  And one of the only things I can think to add is one wire at a time, one connector at a time.  As a whole, it's a little complicated.  One wire at a time?  Not that bad.  You'll get good at the wiring diagram, you'll get good at the wires...

 

It'll be an education you maybe didn't want, but when it's sorted, it'll be very much more 'your' car.

 

Believe it or not, there's been worse done to 2002s.  By a mile.  If that can get unfucked, you can unfuck this.  One wire at a time.  And everyone here will help.  Always.

[mgben]

You will do fine, just remove the alarm and stereo as you planned.  And sort out things from there. 

Where did the PO Mount the fuel pump? And where did that person get the power for it? 

(I ran a wire to my trunk for future Fuel Pump use though I may never need it). 

I have had great service from these guys on wire, relays, and fuse holders. Like @Tdh said you can run a feed to a fuse panel (either near your current one or into your cabin. From there send power to your Fuel Pump Relay and Stereo. 

https://ceautoelectricsupply.com/individual-components/fuse-blocks-fuse-panels-fuse-holders/

Or for one or 2 circuits  I use the DIY Fuse holder kit

It is waterproof and can be mounted near the battery where you get power

https://ceautoelectricsupply.com/product/metri-pack-630-series-atc-fuse-holder-kit/

an amazon crimper is handy to make the crimps. I faked out the 14 ga crimper to work with 12 ga wire 

You see how the tight crimp to the wire and the round crimp to the insulation is pretty professional. 

https://www.amazon.com/IWISS-Harness-Crimping-Computer-Automotive/dp/B01M1YK5FM/ref=psdc_553392_t3_B08CXL4RFQ

(I dislike fuse holders that one finds in parts stores where you have to adapt to their wires. (though they work).)

You put your wire up through the red weather seal.. stick them all the way through, make your crimp, then pull the connector back down into the housing. The fuse plugs into the 2 connectors and great for engine compartment

For a Relay, the crimp tool is also handy, but easier because the connector goes up into the plug (or direct to relay without a plug). 

I am a Mechanical Engineer but figured wiring out, (though I seem to use thicker wire than I need).

Wire by the foot there too. 

Harness tape is great TESA brand. High temp. (fuzzy is for interior )

To protect wires for runs in the engine bay or to make your own harness's this stuff is nice. 

 

[TobyB]

One wire at a time.  You'll soon get a sense of what's added and what's supposed

to be there.  If it's wrapped in hockey tape, that's usually a good sign.

I totally agree- strip out everything not stock, and then fix the stock stuff

that's not working.

The hazard switch is a big problem- causer because it's an add- on

AND it interrupts everything

 

There is a wiring diagram in the FAQ somewheres- probably in the articles section.

It will be so much spaghetti at first, but do this:  figure out which wire is which 

in the taillights.  It'll take all evening the first time, but once you've decoded 

what means what, it gets easier every time.  To a point.

 

Next, connections- the taillights in particular don't make good connection,

so that's good practice at sanding, tightening, crimping and shimming.

 

t

 

[ray_]

By the way, that looks like an aftermarket electronic flasher relay for the turn signals at the left of your pic. There are articles in the tech section on how to properly fit one (tho my car rebelled against it).

 

https://www.bmw2002faq.com/articles/technical-articles/electrical-and-ignition/

 

Just saying your wiring diagram is not going to match what you see on that relay.

 

Good luck to ya!