Turn Signal -Blinks Rapidly

[tomcad95]

My 95 Caddy's right turning signal blinked rapidly for a period of time, now the left signal is doing the same thing. I checked the bulbs, they all look good. Does anyone know what I should check next?

[Cadillac Jim]

Your profile doesn't give the year of your Deville, but I'm going to assume that it has cornering lights and side lights like the Devilles that I am familiar with. Make sure that all these are OK too.

I think we can eliminate the blinker itself because it happened on one side first. Quick blinking usually means the bulb. Cadillac uses a multi-terminal electronic blinker, like most newer cars, and it's not a simple thermal switch blinker like older cars, so it isn't as sensitive to a bad bulb as older cars.

The next think to look at is the multi-function switch inside the steering column. That's a big job so a lot of checking should precede going after that.

[tomcad95]

Your profile doesn't give the year of your Deville, but I'm going to assume that it has cornering lights and side lights like the Devilles that I am familiar with. Make sure that all these are OK too.

I think we can eliminate the blinker itself because it happened on one side first. Quick blinking usually means the bulb. Cadillac uses a multi-terminal electronic blinker, like most newer cars, and it's not a simple thermal switch blinker like older cars, so it isn't as sensitive to a bad bulb as older cars.

The next think to look at is the multi-function switch inside the steering column. That's a big job so a lot of checking should precede going after that.

My 95 deville does have cornering lights, I replaced those blubs, but they don't blink, they just stay on when the blinker is on. I don't recall if they

ever blinked?

[BodybyFisher]

No cornering lights just stay lit when the headlights are on, and you use the turn signal. A fast turnsignal is a bad bulb in the front or the rear, I just got that the other day and replaced a bulb

[Texas Jim]

I agree with Body by Fisher.

Fast blinking is almost always a bad bulb.

Very occasionally it could be a bad ground or a loose wire...but it will still be affecting a bulb and causing it not to blink properly.

[Cadillac Jim]

Never underestimate the number of bulbs in a Cadillac turn signal.

[lothos]

I have a fast blinking on my left turn signal. The bulbs are good. I think the problem is a bad pigtail / socket in the rear tail lights. During the day the lights all work normally, but when the headlights are on the fast blinking occurs, and one of the bulbs doesn't light up when the brakes are pressed.

A new pigtail for the back is pretty low priority for me, haven't changed it yet.

[STSSCOTT]

I have a fast blinking on my left turn signal. The bulbs are good. I think the problem is a bad pigtail / socket in the rear tail lights. During the day the lights all work normally, but when the headlights are on the fast blinking occurs, and one of the bulbs doesn't light up when the brakes are pressed.

A new pigtail for the back is pretty low priority for me, haven't changed it yet.

I also have the same exact problem, only the left blinker like you describe and only when any lights are on including the fog lights, dod you ever get the issue resolved?

thanks

Scott E

[BodybyFisher]

I have a fast blinking on my left turn signal. The bulbs are good. I think the problem is a bad pigtail / socket in the rear tail lights. During the day the lights all work normally, but when the headlights are on the fast blinking occurs, and one of the bulbs doesn't light up when the brakes are pressed.

A new pigtail for the back is pretty low priority for me, haven't changed it yet.

When I say you have a bad bulb, I mean, its not flashing, that happens because the bulb is bad OR because its not making a good connection

[PAUL T]

I have a fast blinking on my left turn signal. The bulbs are good. I think the problem is a bad pigtail / socket in the rear tail lights. During the day the lights all work normally, but when the headlights are on the fast blinking occurs, and one of the bulbs doesn't light up when the brakes are pressed.

A new pigtail for the back is pretty low priority for me, haven't changed it yet.

I had to buy a new socket for my 94 Deville. Mine became high priority when I was pulled over in town by the State Police. They waived the ticket if I fixed it, so it was fixed the next day.

[STSSCOTT]

I have a fast blinking on my left turn signal. The bulbs are good. I think the problem is a bad pigtail / socket in the rear tail lights. During the day the lights all work normally, but when the headlights are on the fast blinking occurs, and one of the bulbs doesn't light up when the brakes are pressed.

A new pigtail for the back is pretty low priority for me, haven't changed it yet.

I had to buy a new socket for my 94 Deville. Mine became high priority when I was pulled over in town by the State Police. They waived the ticket if I fixed it, so it was fixed the next day.

Hi: Glad it was an easy fix.............but what socket did you replace?

Thanks in advance

Scott

Emmans.rs@pg.com

[Logan]

You have to look at the sockets pretty close. Any burn marks indicate a melted ground inside the socket. Pretty common.

Being both side are flashing quick. I suspect a bad turn signal switch in the column. Pretty big job.

That said, it could be a bad flasher unit.

[PAUL T]

I have a fast blinking on my left turn signal. The bulbs are good. I think the problem is a bad pigtail / socket in the rear tail lights. During the day the lights all work normally, but when the headlights are on the fast blinking occurs, and one of the bulbs doesn't light up when the brakes are pressed.

A new pigtail for the back is pretty low priority for me, haven't changed it yet.

I had to buy a new socket for my 94 Deville. Mine became high priority when I was pulled over in town by the State Police. They waived the ticket if I fixed it, so it was fixed the next day.

Hi: Glad it was an easy fix.............but what socket did you replace?

Thanks in advance

Scott

Emmans.rs@pg.com

If I remember right it was the rear top socket. It was as Logan said a bad socket ground. I ran a ground wire as a temporary fix through the socket plastic until I found a replacement. The hard part was that I could not find an exact replacement part for it and had to rework the socket tabs on another year to get it to fit. None of the parts stores had or could not get the correct replacement for a 94.

[Chris]

The hard part was that I could not find an exact replacement part for it and had to rework the socket tabs on another year to get it to fit. None of the parts stores had or could not get the correct replacement for a 94.

I experienced quick flashing (but only on one side) of my sts. Fixed the problem by replacing one of the sockets, but had the same problem as you with aftermarket sockets - the tabs had to be reworked.

Let us know what the problem with you car is!

[JohnnyG]

Rapid flashing like this is usually caused by an overload in the circuit. Pulling too much current can be caused by a bad bulb, which most of you describe, but it's how the bulb fails that is important. In these cases, the bulb filament breaks and becomes shorted back onto itself or the opposite supporting lead causing DECREASED resistance in the circuit, hence more load.

In the case of the bad socket, different failure mode but same result. A carbon path is burned to the next contact in the assembly usually caused by water intrusion into the socket, the combination of the two paths to ground DECREASE the resistance and cause the load on the flasher to increase resulting in rapid (weak) flashing of the bulb.

The fix is pretty much as you all describe, change the bulb or the socket once you figure out which items are responsible.

If the problem is caused by the flasher (unlikely) all bulbs, front or rear would exhibit this rapid flashing right from the start, there would be no question as to which individual position was affected. So now you have two bad bulbs or sockets instead of just one.