• Hi Guest!
    You can help ensure that British Car Forum (BCF) continues to provide a great place to engage in the British car hobby! If you find BCF a beneficial community, please consider supporting our efforts with a subscription.

    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

TR4/4A Elec Flasher/LED bulbs revisited

Dennis Williams

Freshman Member
Offline
Hi All,

Just upgraded some of my bulbs to LED along with an electronic flasher unit for my TR4A purchased from Moss. Everything works great except for one thing: the dash flasher and the clicking of the turnsignals stay on even though they are off at either end. Checked out the wiring and everything seems as it should. Does anyone have a solution on the dash issue?

Thanks!
 
You need a different flasher for those

I purchased the one from Moss that they stocked. It is the one with the ground wire. I just purchased a Tridon EL13 (no ground wire) thinking that might be the problem but haven't installed it yet. Should I try that?
 
I use the EL13 with standard incandescent bulbs. It MAY work for LEDs since it is not supposed to be sensitive to blown out bulbs and/or the amount of current flowing. However, I don't think it was specifically designed for LED use either. It will not hurt to try it but I'd hate to see you open the package up and not be able to use or return it.
 
I thought the flashers work on heat , so with no draw(or very l'il) no heat
 
Out of curiosity, what flasher did they sell you?

I agree, the EL13 is not likely to work with just LED loads. Although it is not thermal in nature, it does require some minimum load (about one incandescent bulb) to operate.

One solution would be to add a pair of dummy loads (one for each side), which should make the EL 13 work. I don't recall for certain what value I used offhand, but 10 ohms, 5 watts should work for the EL13. With a lower resistance (and higher power), even the original thermal flasher would work. I mounted mine up under the dash where they cannot be seen.

Another possible solution would be to rewire the dash lamp to +12v instead of ground. I'm fairly certain that will make the electronic unit from Moss work as desired.

Or just return what you have to Moss, and ask them to supply a flasher that actually works as advertised.

PS, I ran my EL-13 with just the dummy load, the other day on the way to the body shop. Worked fine. I still use incandescent bulbs, but have a relay setup for the rear lamps, so they can do triple duty as turn, stop and tail lamps. The relay coil draws even less than LEDs do, so the dummy loads are required to get the EL-13 to work. (In my case, they also ensure that the relays work even if a bulb burns out.)

 
In that case, I wonder if there isn't something else going on, like perhaps an electrical leak or mis-wiring somewhere. Can you try disconnecting the 'L' lead, with the 'X' and 'P' still connected?

Your car is still wired negative ground, right?
 
In that case, I wonder if there isn't something else going on, like perhaps an electrical leak or mis-wiring somewhere. Can you try disconnecting the 'L' lead, with the 'X' and 'P' still connected?

Your car is still wired negative ground, right?

Yes, negative ground

I bent back the L lead (which leads to the dash light) and plugged it back in. while it did disable the light the clicking continued
 
(which leads to the dash light) and plugged it back in.
Ok, that's a problem. The 'L' terminal should go to the turn signal switch (and through the switch to the turn signals on each side), the 'P' terminal should go to the light on the dash.
https://cecindustries.com/pdfs/EF33RL.pdf

It also would appear that something is drawing current that shouldn't be. Assuming the turn switch is off, the GN wire should be an open circuit. Can you try it again with the lead to the switch (the GN wire) disconnected? Maybe also use a meter to check resistance from GN to ground (with the key off and turn switch off).
 
This is a bit off the original topic of this thread. The original flasher that was in our TR4A when we purchased it 48 years ago was cycling very fast. Rather than order from normal sources I stopped by a Carquest Auto Parts Store and purchased their P/N FSH 550. It has a great normal flash rate and only cost $4.87 w/ tax.
 
This is a bit off the original topic of this thread. The original flasher that was in our TR4A when we purchased it 48 years ago was cycling very fast. Rather than order from normal sources I stopped by a Carquest Auto Parts Store and purchased their P/N FSH 550. It has a great normal flash rate and only cost $4.87 w/ tax.
But now one or more of your turn signals are dimmer than they should be. The reason the old flasher was cycling fast was because the current draw of the bulbs was less than it expected. This is a safety feature, to alert the driver when a bulb burns out; but it can also exhibit when there is too much resistance in the circuit for whatever reason. (A common cause on TR6 is a poor ground connection inside the rear bulb holder, but there are lots of other possibilities.)
The Carquest flasher you got is no doubt a "heavy duty" version, which means it lacks the load sensing feature and hence will flash just fine, even with a burned out bulb (or high resistance). The EL13 and EF33RL are the same way.
 
Randall, I appreciate the good information. I probably have too much resistance in the circuit for whatever reason due to all of the years. All six flashing bulbs seem of normal brightness and equal to each other. I should check voltage drops.
 
Update: removed the led bulbs and replaced them with the stock bulbs. Took out the Moss electronic flasher unit and replaced it with an EL13. Everything works fine once again.

thanks for all your help and input!
 
Back
Top