View Full Version : Electrical Flasher relay question - one indicator too fast
jawn101
10-02-2011, 06:47 PM
So, when I got #2100, the socket built into the under-dash harness that the flasher relay plugged into was completely shattered, and the outer casing to the relay was just plain missing. This means that eventually the terminals were bound to short on something... and today they did. Blew the relay and fuse #6. Replaced the fuse, and after a little research, I picked up an EP-35 flasher relay from Napa. It has the same pinout and voltage and was electro-mechanical to ensure that there was still a clicker. I don't have any immediate plans to go LED in the directional indicators so this was a logical choice for me.
Hooked it up and everything is working OK, with one exception - the left directional indicator is flashing way too fast (almost double speed). The right-hand indicator is normal, and the hazards are as well. Just the left-hand one. It wasn't a problem with the original Lucas relay before I killed it....
Is this likely to be something I've done wrong, something else that was hurt when the short occurred, or just that I've chosen a bad replacement relay and should stop being impatient and get an original one? :)
link to the EP-35 relay for those electrically inclined folks (Dave, lol...) https://napaonline.com/Catalog/CatalogItemDetail.aspx?R=NF_EP35_0325226917
Usually, when one of your ligths is flashing too fast, means one of your light bulbs on that side is out! Check all your lights on that side to make sure all are working properly.
May be you replaced one of your bulbs witth LED wich might not be compatible.
Levy
So, when I got #2100, the socket built into the under-dash harness that the flasher relay plugged into was completely shattered, and the outer casing to the relay was just plain missing. This means that eventually the terminals were bound to short on something... and today they did. Blew the relay and fuse #6. Replaced the fuse, and after a little research, I picked up an EP-35 flasher relay from Napa. It has the same pinout and voltage and was electro-mechanical to ensure that there was still a clicker. I don't have any immediate plans to go LED in the directional indicators so this was a logical choice for me.
Hooked it up and everything is working OK, with one exception - the left directional indicator is flashing way too fast (almost double speed). The right-hand indicator is normal, and the hazards are as well. Just the left-hand one. It wasn't a problem with the original Lucas relay before I killed it....
Is this likely to be something I've done wrong, something else that was hurt when the short occurred, or just that I've chosen a bad replacement relay and should stop being impatient and get an original one? :)
link to the EP-35 relay for those electrically inclined folks (Dave, lol...) https://napaonline.com/Catalog/CatalogItemDetail.aspx?R=NF_EP35_0325226917
stevedmc
10-02-2011, 07:31 PM
Usually, when one of your ligths is flashing too fast, means one of your light bulbs on that side is out!
Or the socket could be dirty. I had the same thing happen about a year ago. The socket was full of corrosion.
jawn101
10-02-2011, 07:35 PM
The bulbs are all working fine, and the flash speed was normal before I replaced the relay so I don't know if it would be a bulb/socket. The indicators in the dash are LED, but that shouldn't matter... should it? The exterior bulbs are all incandescent still. The rear lamps are in boards newly refinished by Hervey.
David T
10-02-2011, 08:29 PM
You probably had the wrong flasher and now you have the right one. Typically the flasher is supposed to flash fast to warn you that a bulb is not working on the turn signals. The flasher for the hazard is not supposed to be sensitive to a burnt bulb and will not fast-flash. The problem can be a bad connection, a burnt bulb, a bulb that is not the right one, corrosion in a bulb socket. You should put on the hazard and see what is not working and start there.
David Teitelbaum
jawn101
10-02-2011, 08:32 PM
You probably had the wrong flasher and now you have the right one. Typically the flasher is supposed to flash fast to warn you that a bulb is not working on the turn signals. The flasher for the hazard is not supposed to be sensitive to a burnt bulb and will not fast-flash. The problem can be a bad connection, a burnt bulb, a bulb that is not the right one, corrosion in a bulb socket. You should put on the hazard and see what is not working and start there.
David Teitelbaum
That's the weird thing though. The relay I had in there before appeared to be the OEM Lucas FL19. When the hazards are on, all 4 bulbs are flashing normally and at normal speed with no issue. When I flick it right, it's all normal and fine. Left, both bulbs flash - but twice as fast. I will examine the left hand sockets/bulbs.....
jawn101
10-02-2011, 09:59 PM
OK, I fixed it. You guys were right, the bulbs were the culprit. In the left hand taillight assembly, the turn signal bulb wasn't an 1156 - it was something "compatible." Replaced it and now the flashers are all fine on both sides. Thanks for the help :)
On the plus side, that means we have a new cross-reference part... the Napa NF EP-35 works quite nicely. The clicker is a little more subtle sounding and actually pretty nice :)
Good Job!
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A little late, but for the benefit of future readers:
Typically the flasher is supposed to flash fast to warn you that a bulb is not working on the turn signals.
Typically the flasher is supposed to flash slow to warn you that a bulb is not working on the turn signals. If a bulb blows, there is less power going through the flasher unit, so it takes longer to heat up the bi-metal strip that breaks the contacts. Similar for: A "low" rated bulb mixed with standards, or, a standard mixed with Heavy Dutys (common on trucks).
To Fast: A Heavy Duty mixed with Standards, or, high amp draw in wiring/connector/short. (Too much draw so heats too fast.)
DMC5180
10-03-2011, 12:55 AM
Good Job!
======
A little late, but for the benefit of future readers:
Typically the flasher is supposed to flash slow to warn you that a bulb is not working on the turn signals. If a bulb blows, there is less power going through the flasher unit, so it takes longer to heat up the bi-metal strip that breaks the contacts. Similar for: A "low" rated bulb mixed with standards, or, a standard mixed with Heavy Dutys (common on trucks).
To Fast: A Heavy Duty mixed with Standards, or, high amp draw in wiring/connector/short. (Too much draw so heats too fast.)
Really, Anytime I experience a burnt bulb or a corroded socket issue, I see a Fast Flash never a slow. Well I take that back It think a have seen where the flasher did not flash. But only turned the indicator on steady. I don't recall if it was a bulb issue or the flasher itself. Not in the Delorean, a different car.
Really, Anytime I experience a burnt bulb or a corroded socket issue, I see a Fast Flash never a slow. Well I take that back It think a have seen where the flasher did not flash. But only turned the indicator on steady. I don't recall if it was a bulb issue or the flasher itself. Not in the Delorean, a different car. OOPS!
I didn't consider a little thing called resistance...each good bulb lowers the resistance causing the unit to heat up faster. And, of coarse, a blown bulb has infinite resistance.
(A corroded socket can go either way, depending...)
:slap: Thanks Dennis!!!
Ron,
I believe Dennis is right, one light out, flasher go faster. Your thinking make sense but it is the other way around.
Levy
================================================== ========
Good Job!
======
A little late, but for the benefit of future readers:
Typically the flasher is supposed to flash slow to warn you that a bulb is not working on the turn signals. If a bulb blows, there is less power going through the flasher unit, so it takes longer to heat up the bi-metal strip that breaks the contacts. Similar for: A "low" rated bulb mixed with standards, or, a standard mixed with Heavy Dutys (common on trucks).
To Fast: A Heavy Duty mixed with Standards, or, high amp draw in wiring/connector/short. (Too much draw so heats too fast.)
Really, Anytime I experience a burnt bulb or a corroded socket issue, I see a Fast Flash never a slow. Well I take that back It think a have seen where the flasher did not flash. But only turned the indicator on steady. I don't recall if it was a bulb issue or the flasher itself. Not in the Delorean, a different car.
Ron,
I believe Dennis is right, one light out, flasher go faster. Your thinking make sense but it is the other way around.
I agree...you must of missed my previous post.
Actually my thinking didn't make sense...I was thinking in terms of a single bulb at the time, ""If the bulb blows, there is going to be less power drawn through the flasher so it will heat slower and therefore flash slower"". Which is correct in itself rather than it being the other way around, BUT, this ignores resistance and the fact that there would be no draw at all (and that it would actually stop) --Brain fart I guess???
All neither here nor there since there are several bulbs, in parallel yet....
FWIW- The part about mixing bulbs is correct (but due to resistance).
I'm getting out of here before I earn another well deserved slap!
oops!
i agree...you must of missed my previous post.
Actually my thinking didn't make sense...i was thinking in terms of a single bulb at the time, ""if the bulb blows, there is going to be less power drawn through the flasher so it will heat slower and therefore flash slower"". Which is correct in itself rather than it being the other way around, but, this ignores resistance and the fact that there would be no draw at all (and that it would actually stop) --brain fart i guess???
All neither here nor there since there are several bulbs, in parallel yet....
Fwiw- the part about mixing bulbs is correct (but due to resistance).
I'm getting out of here before i earn another well deserved slap!
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