• Hey Guest!
    British Car Forum has been supporting enthusiasts for over 25 years by providing a great place to share our love for British cars. You can support our efforts by upgrading your membership for less than the dues of most car clubs. There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Upgraded members don't see this banner, nor will you see the Google ads that appear on the site.)
Tips
Tips

Electrical problem

Share this page

Anthony_S

Anthony_S

Senior Member
Offline
So yesterday I had the TR3 out and about. I had parked at my destination and when it was time to leave the sun had gone down and it was dark. So I turned on my lights as one would do in the dark. The head lights were on but no tail lights. The side markers work just fine and so do the break lights. Also the dash lights would not come on. I thought it all very strange for most of the system to work but not those two things.

Anyone have any ideas on what it might be or what to look at first. I havn't had a chance to look at it yet. Thought maybe I could narrow some things done with your help.

Thanks a bunch!
 
What side markers???

If not for that, I would suspect the in-line fuse that protects the tail light circuit (which includes the dash lights and front marker lights). The fuse holder should be clipped to the edge of the dash, approximately above the shifter (but located above the bottom edge of the dash).

Item 41 in this diagram: https://i258.photobucket.com/albums/hh260...alHints6the.jpg

TR3AschematicfromPracticalHints6the.jpg
 
yeah i thought maybe a fuse...i meant blinkers sorry, not side markers. i will have to check that when i get home. thanks
 
Ah, I see. The blinkers run on the same fuse as the brake lights (plus wipers, fuel gauge & heater), so that makes sense.

Of course once you find the fuse blown is when the fun starts : trying to figure out why it blew.
:devilgrin:
 
Yeah, could be fun or the fact that the fuse is over 15 years old, haha....guess we will see. Thanks for the help Randall.
 
Had the same problem years ago on a TR3. It was the inline fuse behind the dash. Remember in cases like this a multi-meter is your best friend, with a six pack of Bass Ale a close second. Good luck.
 
Don Elliott said:
Randall - My 1958 TR3A (TS 27489 LO) never had a fuse there.
Click to expand...
TS13571L doesn't either. The change point is not clear to me, but it seems to be somewhere roughly around TS38000-40000 as TS39781LO did have it.

The fuse is shown even in Practical Hints 4th ed (with the notation "fitted USA only"), which still shows the switch for the dash lights instead of the later rheostat. So the change point was likely before TS50000 as the 4th ed still showed the pre-50K gearbox, starter, etc. (The 5th edition showed the later versions, and had instructions for filling the gearbox through the side; so it almost certainly accompanied cars after TS50K where the dipstick was deleted and the side plug added.)

I don't have a copy of the 3rd edition, but if anyone else does and cares to check, I'd be interested. In fact, I'd love to have a copy or even just a scan of the 3rd edition, if anyone has one.
 
Anthony,

I suggest always using the electrical schematic to quickly identify problems, then use wiring diagram if needed to further locate/follow wiring routing, connecting points, etc.
Robert
1966 Tr4a
 
Rrbbeerrttoo said:
I suggest always using the electrical schematic to quickly identify problems, then use wiring diagram if needed to further locate/follow wiring routing, connecting points,
Click to expand...
That's an excellent idea, but for the earlier TRs it can be difficult to find the right diagram. There are at least 6 different diagrams (and harnesses), but the books never have more than one or two (and they are usually incomplete and wrong).

For example, I have never found a diagram that shows the heater wiring, or one that shows the way the factory wired the overdrive on TS39781LO.
 
Heaters[actually demisters] and overdrive were options,even if they were factory installed. Back in the 50s automobile electrical smarts were taken for granted by car companies. Bullet proof everything as if one was racing the car.Solder high quality electrical eyelets on all body grounds and bolt them using machine screws with nuts.Hide the connection under the wires.Solder all questionable connetions and seal with shrink tubing. Use dielectric grease on all metal exposed connections.Might sound excessive but 15 extra minutes,might save a tow truck or cop's ticket. Remember- you're using 50+ year old technology. A lot of houses with 50+ year old original wiring have burned down.
 
Hey everyone,

Thanks for the all the help and great ideas on tightening up the system. I am hoping to get to attack a lot of things this winter. Anyways....I found the problem right away, like Randall said....check the fuse, so I did. The wiring to the fuse holder had pulled out on one side. So like you mentioned John, it's a good idea to bullet proof those connections. Took a few minutes to fix and I was back up and running, all lit up :smile:
 
Back
Top