electrical anomoly

[rdssdi]

Took the +2 for an evening ride with my West Highland White Terrier, Buster. He loves the Lotus.

When I turned the Park / Panel lights on the tach stops working. Turn off the Park and Panel lights and the tach turns on.

I will have to study the wiring diagram. Crossed wire I assume, Very funny.

Bob

[John Larkin]

I recently discovered that the interior light switch (which I cannot ever recall using) turned on the ignition circuit. I discovered so much bodged wiring behind the dash that I ordered a new loom. I thank the Almighty that the car never went up in smoke.

Check your wiring soon.

John Larkin.

[neilsjuke]

First port of call is the fuse box check for supplys .If it is not a crossed wire or dirty fuse conection This sounds like it's going to be a bad earth on the baby elan the earth point is on the lower dash bolt to frame so check them black wires and block conectors.
Neil

[rdssdi]

As all the ground connections are new, I doubt a bad ground. Possibly a disconnected ground. The loom is new. I will have a look today. Should be interesting.
At first thought I assume the tach power or ground is being switched off. Could have switched two fused power leads.
Bob

[RotoFlexible]

I like the title of your post. Makes it sound like a minor glitch on the space shuttle...

It does behave as if the tach is grounding through one of those lights, rather than directly to ground as it should be. The tach doesn't draw much current so this is OK as long as the lights are off. When you turn the lights on, suddenly the tach's "ground" is at 12VDC, so it stops working. That's a pretty common failure pattern.

On my S2 the tach's case has to be grounded, meaning that the ground wire to the tach securing stud must be in place and tight. May be the same for you. Throw a temporary direct ground on the tach and see if that fixes the problem. (Or blows a fuse...)

[rdssdi]

I crawled under the dash and immediately saw the ground wire was not attached. It is a .25 QC connector that attaches to a thin metal tab soldered to the tach case.

I ASSUME this was the problem. I did not test it. Will drive tonight and see what happens.

Should be as a separate ground wire held by hand fixed the problem.

Bob

[rdssdi]

John

My +2 was not running when I bought it. It was complete but would have been a good parts car. I restored it as my tenacity got the better of me. Most everything was replaced.

I purchased an updated loom from Autosparks in the UK. I now have 10 fuses, 4 additional relays (ignition, rad fan, power antenna, driving lights) as well as added wiring for the power antenna, driving lights, headlamp pod vacuum solenoid. I also specified deletion of control box (added relays occupy that firewall space now) and wiring for an alternator.

Bob