Page 1 of 1

#1 Flickering Headlights

Posted: Fri Aug 10, 2018 5:13 pm
by Greensand73
Hello....when my car is running and i turn on the headlights, it flickers a little bit. Is this a sure sign the alternator needs to be replaced, or can it be something else ? Any advise will be greatly appreciated
Sandy

#2 Re: Flickering Headlights

Posted: Fri Aug 10, 2018 7:07 pm
by JJC
Sandy: Test your alternator, test your battery, but most importantly, check the wiring to your headlamps. Dash switch, plug-in behind headlamps etc, should be tight with no play. Never heard that 'sure sign' alternator was failing was flickering headlights. I would think car might be hard to start, or red ignition light in speedometer might stay on after you start the car . What kind of E, and how long have you had your beautiful car ?

JC

#3 Re: Flickering Headlights

Posted: Sun Aug 12, 2018 1:08 am
by Greensand73
Hi JC
Thanks for sharing. I was not having trouble starting or running the car due to battery issues. My mechanic kept saying when he turns on the headlamp the light flicker...and it has to be the alternator. the ignition light is not on while running. I was not sure , and thank you for your suggestion. I am going to look into all. On Etypes i have owned them for 30 years..first a series 2 and not i have two series 3 roadsters. one is with a 6 weber conversion, and the other has all the emission control devices removed. They both are two different driving experiences...the 6 Weber feels like a performance race car, and the other is silky 12 cylinder smooth power. Sorry for rambling...on and on....but thanks for asking
Sandy

#4 Re: Flickering Headlights

Posted: Sun Aug 12, 2018 10:28 am
by Series1 Stu
I once had a flickering headlamp and it turned out to be the dip beam filament shaking with the car's vibrations. Somehow it stayed intact although it was broken by the time I got it out.

Could it be as simple as that?

Regards

#5 Re: Flickering Headlights

Posted: Sun Aug 12, 2018 10:34 am
by Greensand73
HI Stuart....thank you. Yes i need to check this and other suggestions posted here before concluding it is the alternator.
:thankyouyellow:
Sandy

#6 Re: Flickering Headlights

Posted: Mon Aug 13, 2018 12:42 am
by JJC
Sandy: I also removed all emission junk. Car always runs great. Webbers are lovely, but never went that route. Feel free to call at any time...I'm sure we could pick each others brains ! LOL

John

917 544 3124

New York City

#7 Re: Flickering Headlights

Posted: Mon Aug 13, 2018 2:15 pm
by PeterCrespin
Greensand73 wrote:
Fri Aug 10, 2018 5:13 pm
Hello....when my car is running and i turn on the headlights, it flickers a little bit. Is this a sure sign the alternator needs to be replaced, or can it be something else ? Any advise will be greatly appreciated
Sandy
On modern cars it often is, but there is flickering and flickering...

Old cars usually flicker for all the reasons stated and the pulsing is between normal and slightly dimmer, due to poor connections, loose filaments etc.

Modern cars do that too, but the reason your mechanic suspects the alternator is because modern connectors are far better and today they often fail due to damaged voltage regulation circuitry. When that happens (as it did on my Super V8 Daimler), they can flicker between normal and dangerously bright, when voltage spikes can ruin the ECU and other expensive electronics. The Series 3 is somewhat intermediate, being neither the old-school S1 system, nor the current ('scuse pun') integrated system either. Guess it could be either type of flickering, but even a dolt like me could figure out several of the most obvious faults in five minutes with a multimeter.

#8 Re: Flickering Headlights

Posted: Wed Aug 15, 2018 8:54 am
by Paul Buckley
When my car was relatively new, in the 70's, it developed pulsing/flickering lights.
I took it to the Jaguar main dealer, Appleyards of Leeds, and they diagnosed a faulty diode in the alternator.
Whatever they did fixed the problem at that time, but now, forty years later, the symptoms have returned!

#9 Re: Flickering Headlights

Posted: Wed Aug 15, 2018 7:39 pm
by Series1 Stu
Paul Buckley wrote:
Wed Aug 15, 2018 8:54 am
forty years later, the symptoms have returned!
Forty years? Is that all? You just can't get decent quality parts anymore......... :P

#10 Re: Flickering Headlights

Posted: Fri Aug 17, 2018 10:59 am
by Ole-xke1974
PeterCrespin wrote:
Mon Aug 13, 2018 2:15 pm
but even a dolt like me could figure out several of the most obvious faults in five minutes with a multimeter.
Sometimes a voltage drop in a connector or switch will cause heat which can be felt with a finger. Maybe not an exact fault finding method, but if you detect a warm/hot connector or switch, it's most likely due to a bad connection.