Good evening all. I have a light bar mounted to my land cruiser. Has been working a treat. Camped up the other night and a fellow camper alerted me to the fact that the bar was flickering on and off intermittently. Switched on the ignition and put lights on high beam and the light bar shone as it should. Switched off ignition and lights and the a couple of the LEDs flickered on and off. I covered the bar so others would not be annoyed. In the morning there was no flicker, but when I checked to see what the bar was doing, there was no light at all on the bar when headlights were on high beam. I have replaced the relay and checked the fuses but still no light. Can away offer me some more ideas before seeing an auto electrician. Cheers. Daz
Tony Bev said
11:34 PM Oct 3, 2016
Hello dazz49 I am not an electrician
Many years ago I had more or less the same symptoms while running two spotlights from the one relay, I had received in a kit. (I had to disconnect the wires when the spotlights decided to stay on, when I was on a rough dirt track)
The problem turned out to be the relay
You mention that you have replaced the relay I ask the question, have you made sure that the second relay is actually working
There is also a post on here somewhere, about certain model vehicles, having a computer sending out a signal to see if there is a connection to the lights. This signal is strong enough to make the LED lights flicker
Hope this info helps others to come forward
rrobor said
01:09 AM Oct 4, 2016
As far as I am aware, Toyota does not have the Led flicker symptom. Its mainly European and a few US models. Not seeing the circuit of the thing, its difficult to say, but it seems to suggest the drive to your relays which was causing the relay to chatter. Perhaps water in it ETC.
Problems like that don't last long before something gives up. You should be able to hear the relays latch when switched on, if you don't, trace back to where the power comes from. One word of warning, I wouldn't drive much in the dark till you trace what's up. I once had a slack rivet in a fuse holder doing this sort of thing and it scared the whatsits out of me when all the lights went out. I was lucky I was following another car at the time, but you cant trust to luck.
patrol03 said
09:21 AM Oct 4, 2016
Suggest you disconnect wiring and connect 12v directly to light and check that it is operational then check out your circuit with your multimeter.
T1 Terry said
11:11 PM Oct 5, 2016
Another possible is a poor earth return circuit, sounds strange but I've seen the same thing happen with internal LED lights and it finally lead back to a poor negative return to the battery from a separate device. There is a member who posts here has recently had such a problem with tail lights and clearance lights I think, the lack of a connection between the inverter and vehicle body was the cause I believe.... leds present some strange problem as they require very little current/voltage to produce some light
T1 Terry
PeterD said
05:53 PM Oct 6, 2016
I think Darrell is talking about a driving light, not low current indicators like some are talking about. LED driving lights draw serious current and do not operate through the indicator monitoring systems like the caravan LEDs do.
-- Edited by PeterD on Thursday 6th of October 2016 05:55:07 PM
dazz49 said
11:49 AM Oct 7, 2016
A quick update. It is a led driving light bar. I replaced the new relay with the old one and found next morning the bar lit up on high beam but not brightly. I replaced the relay again with another and still the light works but no where near bright enough. I also now think it must be a crook earth and will chase that up
Currently in the nt with very limited internet. Will keep advising of results and read replies when I can. Thanks for all input so far. Cheers Daz
dazz49 said
08:11 PM Oct 7, 2016
Checked the power supply 12.6 v at the light. Must be a problem with the light itself I think
Tony Bev said
09:43 PM Oct 7, 2016
Hello dazza49
I am not an electrician, so this is just one person talking to another, while waiting for the electric teckies to come forward
Glad to see that you have nearly got it sorted
The original flickers with the switch off, means to me that you were getting power to the LED light from somewhere, faulty relay/switch etc
The LED light being dim when you fitted another relay, means to me that the Led light is damaged, or the relay was not large enough to give the amps which the LED light requires
With the LED light no longer working with 12.6 volts going to it, could mean that it is dead or, that something inside the LED light is damaged, which could be repaired
Perhaps when you refit a new/repaired LED light, and there is still flickering, that you disconnect it, until an Auto Electrician can have a look the wiring system
What I have learned from your post is that a flickering LED light should be disconnected, and not just put a blanket over it, so thanks for that
rrobor said
11:53 PM Oct 9, 2016
It sounds like the drive to the relay not the relay itself. The relay will switch with a 12V supply to the coil. The normal position for the relay is off or open. Apply 12V to the coil and the contacts close. If for some reason the voltage was low to the relay coil it could cause the relay to loosely close and you could get the points arcing. Switching the relay gives you new clean contacts and, for a time, it seems a bit better. That will not last. All you are doing is destroying another relay. Stick a screwdriver on top of the relay and put your ear to the handle and have someone switch the light on. You should hear a good clunk as it clicks on, if not you need to find out what's wrong with that 12V line.
dazz49 said
12:12 AM Oct 11, 2016
I thought it must have been the light itself. But today I am in Katherine and disconnected my light bar and reconnected one on another vehicle. Same result. Light bar not fully lighting up. Looks like a job for an auto electrician. Cheers Daz
Hello dazz49
I am not an electrician
Many years ago I had more or less the same symptoms while running two spotlights from the one relay, I had received in a kit.
(I had to disconnect the wires when the spotlights decided to stay on, when I was on a rough dirt track)
The problem turned out to be the relay
You mention that you have replaced the relay
I ask the question, have you made sure that the second relay is actually working
There is also a post on here somewhere, about certain model vehicles, having a computer sending out a signal to see if there is a connection to the lights.
This signal is strong enough to make the LED lights flicker
Hope this info helps others to come forward
Problems like that don't last long before something gives up. You should be able to hear the relays latch when switched on, if you don't, trace back to where the power comes from. One word of warning, I wouldn't drive much in the dark till you trace what's up. I once had a slack rivet in a fuse holder doing this sort of thing and it scared the whatsits out of me when all the lights went out. I was lucky I was following another car at the time, but you cant trust to luck.
T1 Terry
I think Darrell is talking about a driving light, not low current indicators like some are talking about. LED driving lights draw serious current and do not operate through the indicator monitoring systems like the caravan LEDs do.
-- Edited by PeterD on Thursday 6th of October 2016 05:55:07 PM
Hello dazza49
I am not an electrician, so this is just one person talking to another, while waiting for the electric teckies to come forward
Glad to see that you have nearly got it sorted
The original flickers with the switch off, means to me that you were getting power to the LED light from somewhere, faulty relay/switch etc
The LED light being dim when you fitted another relay, means to me that the Led light is damaged, or the relay was not large enough to give the amps which the LED light requires
With the LED light no longer working with 12.6 volts going to it, could mean that it is dead or, that something inside the LED light is damaged, which could be repaired
Perhaps when you refit a new/repaired LED light, and there is still flickering, that you disconnect it, until an Auto Electrician can have a look the wiring system
What I have learned from your post is that a flickering LED light should be disconnected, and not just put a blanket over it, so thanks for that