Need help with flasher relay issue

[dascoupeguy]

Here's a long question for you... Hopefully a short answer will follow!

One of my 72 3.0cs (car #1) has an issue... The flasher relay will work when the emergency flasher button is pressed... All lights work... the red flasher button, the green turn signal indicator on the dash and all four corners... they work perfectly.

However, when the turn signal indicator is used (R or L) the green dash 'telltale' will flash only once then quit, but the flasher continues to operate and flash the R or L signals.

In the other 72 coupe (Car # 2), all lights work perfectly. And after swapping the flasher units to test, both flasher units work perfectly in car #2. So the problem is not in the flasher relay. I even tested a third relay to be sure.

I am at a loss as to why the dash 'telltale' does not continue to flash (in car #1) when using the turn signal. Don't know if it is a contact problem in the turn signal switch itself or a wiring issue, ground or???

Any ideas? Thanks, DCG

 

[Ohmess]

It sounds like switching on the turn signals is changing the ground on your circuit.

First thought would be to check the grounds under the dash, to ensure a good solid contact and to ensure a common ground point. Move any stray grounds to the common ground on the left front fender wall. In particular, if you have an aftermarket stereo, it should be grounded to the common ground to avoid transients teaming through your car. Also, while contorting yourself underneath the dash, look for frayed wiring, crappy connectors, etc.

If that yields nothing, check the wiring to the turn signal switch in the stalk. If you don't see anything, measure the resistance from the ground on the stalk to the common ground to ensure good continuity. Then measure the ground contacts on the relay to the common ground and compare the measurements; they should all be very close and indicate little resistance (i.e., good continuity).

Next, step would be to check these same measurements while operating the circuit (first flasher alone, then flasher with turn signal) and see if you can isolate whether the ground appears to change. If resistance measurements show no change, you can also measure voltage from the flasher relay to ground to determine whether voltage drops when the turn signals are engaged (obviously, this will only measure voltage with the flashers engaged and operating). You may also want to measure the other way, checking whether voltage on your turn signal ground changes when your turn signals are on and you then engage your flashers.

I don't have my wiring diagram handy, but you may need to expand outward depending on what else is on that circuit.

 

[jmackro]

when the turn signal indicator is used (R or L) the green dash 'telltale' will flash only once then quit, but the flasher continues to operate and flash the R or L signals.

Yea, that's one of the more common problems on e9's, e3's, and 2002's.

You can fool with bulb wattage, grounds, socket corrosion, contact pitting inside the flasher.... but a simpler solution is to just install an electronic flasher which is insensitive to current draw. My own experience with this is discussed toward the end of the thread at: http://www.e9coupe.com/forum/showthread.php?t=12371&highlight=signal After installing a cec EF-33 flasher, that cost $13 at my local NAPA store, my dash telltale works just fine.

 

[dascoupeguy]

Yea, that's one of the more common problems on e9's, e3's, and 2002's.

You can fool with bulb wattage, grounds, socket corrosion, contact pitting inside the flasher.... but a simpler solution is to just install an electronic flasher which is insensitive to current draw. My own experience with this is discussed toward the end of the thread at: http://www.e9coupe.com/forum/showthread.php?t=12371&highlight=signal After installing a cec EF-33 flasher, that cost $13 at my local NAPA store, my dash telltale works just fine.

Jmackro... thanks for the info... before I rush down the Napa store, is the relay you referenced 'plug and play'? DCG

 

[dascoupeguy]

It sounds like switching on the turn signals is changing the ground on your circuit.

First thought would be to check the grounds under the dash, to ensure a good solid contact and to ensure a common ground point. Move any stray grounds to the common ground on the left front fender wall. In particular, if you have an aftermarket stereo, it should be grounded to the common ground to avoid transients teaming through your car. Also, while contorting yourself underneath the dash, look for frayed wiring, crappy connectors, etc.

If that yields nothing, check the wiring to the turn signal switch in the stalk. If you don't see anything, measure the resistance from the ground on the stalk to the common ground to ensure good continuity. Then measure the ground contacts on the relay to the common ground and compare the measurements; they should all be very close and indicate little resistance (i.e., good continuity).


Next, step would be to check these same measurements while operating the circuit (first flasher alone, then flasher with turn signal) and see if you can isolate whether the ground appears to change. If resistance measurements show no change, you can also measure voltage from the flasher relay to ground to determine whether voltage drops when the turn signals are engaged (obviously, this will only measure voltage with the flashers engaged and operating). You may also want to measure the other way, checking whether voltage on your turn signal ground changes when your turn signals are on and you then engage your flashers.

I don't have my wiring diagram handy, but you may need to expand outward depending on what else is on that circuit.

Thanks... will get out the 'ol multimeter and check things... DCG

 

[jmackro]

Jmackro... thanks for the info... is the relay you referenced 'plug and play'?

Yes, no wiring changes are needed. The only wrinkle is physically mounting it - the cec EF-33 flasher is cylindrical in shape, while the stock flasher is box-shaped and has a little hook on it. I just used a tie wrap to mount my cylindrical EF-33 to the piece of sheetmetal that my stock flasher used to hook onto. But other than mounting it, there are no other gotchas.

 

[Ohmess]

Yes, no wiring changes are needed. The only wrinkle is physically mounting it - the cec EF-33 flasher is cylindrical in shape, while the stock flasher is box-shaped and has a little hook on it. I just used a tie wrap to mount my cylindrical EF-33 to the piece of sheetmetal that my stock flasher used to hook onto. But other than mounting it, there are no other gotchas.

So, the issue was internal to the flasher unit?

 

[jmackro]

So, the issue was internal to the flasher unit?

Well, I don't know. Those flashers worked when new, and my 40+ year-old flasher would work for a few days if I removed the cover and polished up the contacts with sandpaper. So does that mean the "problem" was internal to the flasher, or that the impedance of the wiring-bulb-socket-ground system had changed? Beats me - I fixed it for $13 and moved on, without too much philosophizing.

 

[bluecoupe30!]

Flasher follies

Had same issue some months ago. Traced every wire in turn signal circuit. Cleaned up many weak connections, found corrosion at ground contact on front signal assemblies. But final piece of the puzzle was all brand new, correct bulbs from the dealer. Just my experience.
Mike

 

[Stefan]

Had same issue some months ago. Traced every wire in turn signal circuit. Cleaned up many weak connections, found corrosion at ground contact on front signal assemblies. But final piece of the puzzle was all brand new, correct bulbs from the dealer. Just my experience.
Mike

+1 for replacing all bulbs to new and fresh ones.

That worked for me also, even though the existing ones (probably original from factory) still worked.

 

[Tyler]

Same issue here - all external indicators work but the green dash light only flashes 3-4 times when turning left. Right turn it all works fine.

Jay - the cec EF-33 flasher appears to be three-prong vs. stock of 4-prong or was yours different?

I'll check bulbs and grounds in the meantime.

Thanks everyone.

 

['69 2800cs]

I have the EF33 waiting to go on and was also wondering about the 4 vs. 3 plug wiring.

I found this over on the '02 board....the EF33 is indeed marked XPL so it should be a simple plug and play.

My issue is the turn signal lever needs to be in just the right position for the turn signals to work.



Get a 3 prong flasher unit with terminals marked "X," "P" and "L." There are different spec units available. Littlefuse makes a unit designated "EFL 300" that is appropriate- if you cross reference to that, you will get the right part. The X terminal is the +12V input, the P terminal output drives the flasher indicator in the instrument panel, and the L terminal drives the load (bulbs).

In the '02, the typical flasher wiring is comprised of a 4-wire circuit, including the following: brown (ground, of course), black/white (instrument panel flash indicator), green/violet (+12V) and green/yellow (load- bulbs). The brown ground wire is not used with the electronic flasher. The configuration of the male spade connectors on the flasher unit is very similar to a headlight connector. A female headlight connector with pigtails (available at most any auto parts store) works fine as an adaptor between the 3-prong electronic flasher unit and the '02 flasher connector. Note, however, that for a few bucks, many auto parts stores can provide a more precisely fitting plug intended specifically for turn sign flashers.

Just solder .25" male spade connectors to the pigtails (use shrinkwrap to cover your solder connections, of course) and plug into the '02 connector. Connect the "L" terminal to the green/yellow wire, "X" to the green/violet wire, and "P" to the black/white wire.

 

[jmackro]

Jay - the cec EF-33 flasher appears to be three-prong vs. stock of 4-prong or was yours different?

Tyler:

Yes, you are correct. My stock flasher had 4 terminals:

49 power in
KBL indicator light on the dash
49a pulsing +12v out to exterior bulbs
30 ground

The cec EF-33 flasher has only three terminals because it does not need a ground connection. The terminal labeling is:

X power in
P indicator light on the dash
L pulsing +12v out to exterior bulbs

I'm about 96.2% sure of the above information.

 

[Tundra]

I had the same problem that started 3 days ago. Here is what worked for me:

I had taken out one of the front turn lighting housing out to change the seal(not that you have to). I had disconnected the three wires, one is ground, one is connected to the turn signal relay ( I think) and the third is connected to the on/off light switch. The ground wire is obvious. The other two are each connected to their own prong on the turn signal housing.

When I put everything back together is when the problem similar to yours started. I then took out the turn light out again and switched the two wires form their respective prongs and everything worked perfect again. Not sure if in my case it was a fluke that everything worked again or if it was indeed the problem.