S4 Elan (Federal) Wiring Issues

[hubrick]

Hello All,
Well, it's been 4 months since I first contacted you trying to sort out an ignition wiring problem back in March. I got my Elan in February, a 70 S4 (Federal) convertible, Car# 7002040030K, previous owner disclosed some electrical problems - headlights didn't work, lights mechanicalaly held down, horm, wipers, turn signals, all inop - he suspected a faulty ground. I drove it around a few times, then it quit and left me stranded. No power to the coil. Ran a jumper from the fuse block to the coil and it starts and runs (although it won't start until I release the key from the spring loaded start position), and I've been driving it around that way about once a week since.

Now that I've finished two other cars I've been working on, this week I'm diving back into the Lotus. Many electrical questions. I have the workshop manual, the workshop Series 4 wiring diagram, and I've been reading through many previous posts to try to resolve questions. I'm trying to get the lights and the turn signals working so I can drive it, then I'll work on the windshield wipers, horn, windows, emergency flashers later as I get to them.

The wiring on this car is a real mess - many dangling wires, many wrong color wires, many electrical taped splices, several in line fuses. My first impression is I need a new wiring harness. What do y'all think, is that much more trouble than it's worth?

Here are some individual system issues that I've discovered so far.

1. Headlights - it's very hard to tell what my system is supposed to look like and how it works. What is right and wrong on the diagram for my car? I don't see the headlamp micro-switch that's on the diagram anywhere in the car. From what I've read, that switch has moved from the front of the car on the light buckets to the vacuum switch behind the dash for the Federal car. Only there's no wiring to my switch, just a white jumper wire from one terminal to another. The vacuum nozzles on the switch are broken off, the vacuum tubing is there.

The wiring diagram shows the smallFailsafe Headlamps box in the upper right hand corner, but there is precious little information there. Can someone explain what that little box is trying to tell me. The wiring diagram shows the Headlamp Flasher Relay, Unit, and Micro-Switch. I haven't found any of those things on my car - are they on my Federal car, and if so, where are they? Also, if so, I've never heard of a headlamp flasher in any of my other little British cars, so how does it work, what is it's purpose? I can't see that it does anything from the diagram.

The Workshop Manual, Section M, page 106, in a special paragraph for Failsafe Headlamp cars, states "headlamp illumination can only ever be obtained with the ignition on". So why is it that the wiring diagram shows a path to power the headlights, and with the ignition switch off and the Lamp rocker switch on, I get power all the way to the Main and Dip headlamp relays. The only thing keeping those relays from powering the headlights is there's no ground through the black with red stripe wire to the micro switch. Seems like if I just grounded that wire, the lights would work. The Manual also says the parking lights work without the headlights on apparently depending on the position of the vacuum switch and micro switch. My parking lights work with the Lamp rocher switch turned on. There's no indication of the microswitch unless that's it in the Failsafe Headlamps box at the upper right hand corner.

2. Horns - that's an easy one. They're not working because they're missing.

3. Turn signals. Well, they didn't work before, but once I started poking around and checking for power through the system, they started working. Sounds like the flasher is only clicking once, and the lights are blinking very rapidly like there's a bulb out somewhere, but no, all the bulbs are working. I'm thinking the flasher is bad. Yes? The indicator warning light bliinks very dimly in the Speedo when the turn signals are flashing. However, the indicator warning light stays on bright with the Lamp switch on (ignition off). Not supposed to be any power to that light from the headlamp system. Must be a crossed wire or a bad ground somewhere.

4. Ignition. I'll save that long discussion for another post.

Any help with these things would be appreciated. Thanks in advance.
Cheers,
Rick
70 Elan

[Andy8421]

IMO, one of the best things you can do to improve reliability on the Elan is replace the wiring harness. Just have a scan through this forum for the number of electrical problems owners have. This is particularly the case if the existing loom has been 'improved' by a previous owner.

[sprintsoft]

Hi Rick,

I agree with Andy, I think that the large scale of disfunction you are faced with and corrections to unknown wiring mods that you will have to spend time working on means that fitting a new wiring harness will actually be LESS work.

From what you report you will have to remove the dashboard anyway to fix these issues, then you get the chance to check the switches and instruments at the same time.

I would be worried to drive the car with only the lights and indicators fixed as you proposed, there would be too many problems remaining, and you really don’t want to risk any sort of fire in there, that would be a whole lot worse to deal with.

Iain

[hubrick]

Yes, thanks. Pretty much the same way I'm thinking. Lots of peace of mind with a new harness.

Anybody have any ideas on the corrections to the workshop manual's Series 4 wiring diagram compared to what my car actually has, particularly the headlights. It will be pretty tough to put in a new wiring harness without a correct wiring diagram.

Cheers,
Rick
70 Elan S4 Convertible

[RichardHawkins]

Rick,

I am sorry to agree with the others, but when I first started work on my Elan (1968 S4) the wiring horrified me, dangling wires, wires with burnt insulation, an additional clock that someone had fitted very roughly. I decided I needed a new dash and a re-wire, but then mission creep set in and I started to “improve” things, more fuses (23) and relays (10), the amount of work just kept expanding. Whilst I still think this will be an improvement I would advise caution before setting out to improve things, perhaps standard with just new wire is more sensible.

Hope this helps,

Richard Hawkins

[Jentwistle3]

I’ve been working through some similar issues on my S2 as my electric headlamp pod project has exposed numerous “improvements” to the original wiring. IMO the wiring on the Elam, on the S2 at least, was substandard from the get go - incorrect use of wiring colors per the British standard at the time, many unfused components, convoluted ground circuits, etc. Even though everything works on my car I am still tempted to replace the harness.

Fixing wiring issues one at a time is not fun. Starting from scratch with a clean harness looks like a lot of work but will likely save you time in the long run. The only other alternative would be to make your own harness from scratch following the correct wiring codes and ensuring that everything is properly fused. This will be a ton of work but you will know in the end that the car is electrically safe and sound.

[hubrick]

Thanks for another couple of replies, all votes in favor of a new wiring harness. I'm not inclined to make improvements or to build my own, so I'll be happy with buying, removing, and installing a new standard harness. I'm even thinking I'll rebuild the mechanical fuel pump and eliminate the electric pump that's currently wired into the ignition switch and running the car.

Still no replies from anybody about getting a correct wiring diagram for my Failsafe Headlamp Series 4 (Federal) car. Can anybody at least tell me what's different from the Series 4 diagram that's in the workshop manual?

Thanks,

Rick
70 Elan S4 Convertible

[pharriso]

Still no replies from anybody about getting a correct wiring diagram for my Failsafe Headlamp Series 4 (Federal) car. Can anybody at least tell me what's different from the Series 4 diagram that's in the workshop manual?

Thanks,

Rick
70 Elan S4 Convertible

Rick, see viewtopic.php?f=38&t=30133

Get used to the search function on the site or google search (e.g. site:lotuselan.net/forums federal headlight), there’s a lot of info on this site already.

WRT to a new wiring harness the only ones available are for non-federal cars. What rear lights does your car have? US red only or uk red/orange?

[pharriso]

I'm even thinking I'll rebuild the mechanical fuel pump and eliminate the electric pump that's currently wired into the ignition switch and running the car
Thanks,

Rick
70 Elan S4 Convertible

Definitely disagree on that as an electric pump decreases cranking time & helps with hot fuel handling, I just put one in!

[sprintsoft]

Phil,

not to hijack Ricks thread but I would be very interested to hear your experience with hot starting and if the new pump fixed it or how much it improved, maybe worth a new topic? it’s a perennial issue for many, including me!

Iain

[hubrick]

Hello All,
More progress. Phil Harrison has sent me several pictures and a wiring harness diagram from as Federal +2 model that is helping and a home made color coded diagram for a Series 4. So now I have 3 different ones, with some correct features on each one. Big help, making progress. Together with a previous owner who was happy to run new wiring, it's quite a challenge sorting everything out.

So the Federal +2 diagram shows the UB10 turn signal relay box not shown on the WSM diagram. I finally found it yesterday althiough I can only see wires connected to one side. Does anybody recognize this connector and batch of wires in the attached picture? It's wrapped up under the dash not connected to anything, wiring colors don't match anything in any of the diagrams, and I've found a few of the wires connected to the UB10 box - a couple just to the mounting screws.

Still trying to pull the dash farther away so I can see/get my hands behind it to test wiring connections for the wipers and windows that still don't work. Any ideas there on what's causing the dash to be held up somewhere in the middle - I think it's the heater pull knob and wire, I'll dive into that tomorrow.

Cheers,
Rick
70 S4 Elan Convertible (Federal)

[lotusfan]

Hi Rick

''Does anybody recognize this connector and batch of wires in the attached picture?''

My initial reaction was that it is the wiper motor connector but the wire colours are wrong, if it was for the wiper motor they are mostly green with another trace colour.

Phil will sort you out, he's a clever chap!!

[pharriso]

Hi Rick

''Does anybody recognize this connector and batch of wires in the attached picture?''

My initial reaction was that it is the wiper motor connector but the wire colours are wrong, if it was for the wiper motor they are mostly green with another trace colour.

I recognise the wiring colors, that's a generic radio harness, see the attached.

Crutchfield_RadioHarness_120701761.PDF

(92.74 KiB) Downloaded 254 times

[hubrick]

Thanks for identifying the radio wiring harness, I'll attempt to remove it this afternoon.

I received a reply from a wiring harness maker about making me a special harness for my 1970 S4 Elan Convertible (Federal spec) car. They said they would be happy to if I supplied a used one as a model.

So, my question, does anyone have an original wiring harness that's been removed from your car that I can send to them to have one made. Heck, they'll probably even start offering to make them for other people that might need it too, that would be a big improvement for anybody else that wanted to replace their wiring harness.

Cheers,
Rick

[steve lyle]

Rick,

My '72 Sprint is very similar to your car. Your situation is similar to mine as of last summer. Several circuits on my car weren't working, my harness had been highly modified/butchered, and a replacement harness, or even an "as designed" schematics were not available.

I wouldn't make this suggestion to just anybody, but It's clear from your well-written posts, and your taste in classic cars, that you have above average intelligence, so here goes: Pull your dash off, and rewire it. It really isn't that difficult. The harness to the rear of the car is likely good - most people don't mess with that. The under-bonnet wiring is even simpler than the dash wiring, so if it's in bad shape it's not a big deal to redo, either.

Elan wiring, even for a late Federal car, just isn't that complicated. The worst part is the DB10 relay, and there are plenty of sources on the Internet that go into great detail on that. With Phil's diagrams, some decent tools, and this forum you'll be able to pull it off.

My process was to:
1) Get the dash off the car. Kinda fiddly, but we can walk you through that. Set it up on a workbench.
2) On my dash, I just removed the dash harness in it's entirety. Take pictures and make notes if you'd like, but in my case I didn't trust what was already there.
3) Start with the ground - I used a 14 gauge wire for the main ground run, then spliced into that for individual components. Use a ring connector at the lower right dash mounting screw, and run it up and across the dash on the back side to the far right.
4) Similarly, run 14 gauge wires for brown (always hot), white (hot when running), green (fused white), purple (fused brown) and orange (my pick) for fused accessory (white/purple). Map out how you want your electrics to work (i.e., do you want the windows to function always on, or only when the key is on 'run'?) and splice into the appropriate power circuit for that component.
5) I took the opportunity to upgrade to a modern fuse holder with 6 mini-blade fuses. Separate fuses for green, purple, and orange, and dedicated fuses for the rad fan, the headlight power, and parking/running lights. Not stock, but when you're driving a car made out of flammable material, I'd recommend it.
6) I also followed Phil's lead in using Mate-N-Loc connectors. I used these to enable me to eliminate bullet connectors for any circuits that would have to be disconnected to get the dash off again. Bullet connectors really aren't made to be easily disconnected. This came in handy when I DID have to take the dash out again to fix the one bug I missed in testing - when I turned on the panel light, the headlight relay got energized (a diode solved that problem).
7) Give some thought to how the circuits run - some can go from the firewall hole straight back over the heater to the dash. Others will go from the firewall to the column switch (on a Sprint, not sure about your car) and some to the firewall hole to the DB10 or the left side of the dash. I could have done better planning there.....maybe I'll clean it up a little next time I'm in there...

Once you think you've got the dash wired up correctly on the bench, hook it up to power (through appropriately fused power circuits) and ground, and test it out. (watch out for the panel light energizing problem!)

I upped the wire gauge to the window motors to 14 - they now run up/down as quickly as a modern car's - before, they wouldn't even get the windows all the way up. Most other circuits were 16 or 18 gauge. 14 for big power hogs like headlights and radiator fans.

I used the original loom wrap (non adhesive) for under the bonnet, but a more modern soft wrap behind the dash. But lots of options there.

I used velcro strips to hold the loom together while working on it, before removing the strips as I wrapped it when done.

Diagram it before, during, and after, and write up a description that will come in handy when you've forgotten exactly what you've done at some point in the future.

When you get done, everything will work and you'll know exactly how it was done. It's a beautiful thing.