Car blinker system (US) - Page 1
Forum section: electronics / beginners

author: aurmer
author_rank: Regular Contributor
timestamp: November 05, 2016, 03:53:07 pm
content: I had to replace my tail light blinkered socket because even a new bulb didn't work. Unfortunately, after installing the new socket, the light works great, but the system itself is still blinking twice as fast, as to indicate a mal functioning light.Google only told me time and again "your light is out", but I am asking, what does the system use to determine whether or not the light is out? Current sensor? Other?Thanks for any advice.

author: cowana
author_rank: Frequent Contributor
timestamp: November 05, 2016, 03:56:43 pm
content: Usually a current sensor.Some of the LED replacement bulbs you can buy market themselves as 'CAN Bus compatible', meaning they have a load resistor meaning they draw a similar current to a regular incandescent bulb.

author: Adam60
author_rank: Regular Contributor
timestamp: November 06, 2016, 12:28:30 am
content: Younever said what year, make and model the vehicle was so hard to give you a good answer. If we know what generation of flasher you have, answer will be pretty accurate. If you are blinking fast on one side, you still have a problem. Measure the voltage at the socket for the ground side of the circuit when it is flashing. There should be no voltage. If there is, you have a bad ground. Measure thevoltage input on both sides and use an average if you can. Is there much of a difference? Is the new socket you put in soldered connections or crimped. If crimped, make sure connections are good.

author: Brumby
author_rank: Unknown
timestamp: November 06, 2016, 12:22:53 pm
content: My guess is you've used an LED 'globe' on a system that uses a current driven flasher can - the less current drawn, the faster the flashing. This is an intentional design feature - for the sole purpose of letting the driver know there is a problem.Assuming all lights are working, the lower current draw from an LED 'globe' will cause the symptoms you are describing.

author: NottheDan
author_rank: Frequent Contributor
timestamp: November 06, 2016, 02:30:42 pm
content: Are the LED kits road-legal over there?

author: CatalinaWOW
author_rank: Super Contributor
timestamp: November 08, 2016, 03:09:22 am
content: You didn't state the age of the car, but older cars used a thermoelectric flasher system. The light current was passed through a heater wire wrapped around a bimetal strip, which opened the contact as the bimetal strip heated. It then cooled and closed the contact.In these systems a heavier load would cause the light to flash faster. In fact the extra load of paralleling in a set of trailer lights triggered this behavior. And created a market for heavy duty flasher modules which flashed at an appropriate rate when attached to a trailer, but flashed slowly and deliberately when the trailer was not in use.Due to the conservative nature of the auto industry, I suspect that this behavior has been emulated in newer electronic versions. A fast flash would normally indicate higher current, possibly from a possible partial short to ground.

author: Brumby
author_rank: Unknown
timestamp: November 08, 2016, 03:31:19 am
content: In Australia we see faster flash rates when a globe has failed - ie, areducedload.

author: Cliff Matthews
author_rank: Unknown
timestamp: November 08, 2016, 12:54:48 pm
content: Basic enough to roll your own..http://www.instructables.com/id/Simple-Motor-Bike-indicater-Flasher-unit-in-a-TIC-/

author: Brumby
author_rank: Unknown
timestamp: November 09, 2016, 02:05:08 pm
content: Also in Australia is the requirement that the flasher system makes an audible indication. The old thermal contact can makes a clicking sound, so that the driver doesn't need to look at anything to know the flashers are operating. A silent electronic solution would not comply.

author: Zero999
author_rank: Super Contributor
timestamp: November 10, 2016, 10:57:11 am
content: Quote from: NottheDan on November 06, 2016, 02:30:42 pmI don't see why not, as long as they comply with the relevant regulations. If the flash rate is too fast/slow, then it won't be legal but otherwise it should be fine.About 5 years ago I had an accident on my motorcycle and damaged one of the indicators. The lamp holder was broken, even though the rest of the assembly was fine, so I removed it and replaced it with some orange LEDs and a suitable series resistor and glued it back together. The indicator worked fine but flashed too quickly so it failed the MOT as a result. I added a suitable resistor in parallel with the LED indicator, so it flashed at the correct rate, sent it in for the MOT and it passed.

author: Seekonk
author_rank: Super Contributor
timestamp: November 10, 2016, 11:27:53 am
content: Quote from: Cliff Matthews on November 08, 2016, 12:54:48 pmThat circuit likely won't work with a LED unless some resistor is placed across the LED. It wouldn't have to pull a lot of current, just enough to let the capacitor charge to a higher voltage. The LED would act like a zener and there wouldn't be enough gate voltage for the FET. If battery voltage was high enough and the FET had a low gate voltage it could work, but I wouldn't want to be stuck on the side of the road hoping for the best.

author: rbm
author_rank: Regular Contributor
timestamp: November 11, 2016, 01:51:35 am
content: Quote from: Brumby on November 09, 2016, 02:05:08 pmHa, like audible feedback is going to alert the driver to an operating flasher that needs to be cancelled. Not likely to work in North America what with all the distracted drivers. I can't tell you how many time I see people driving along for kilometers with their flasher going and not making any lane change or any exit in the vicinity.

author: Brumby
author_rank: Unknown
timestamp: November 11, 2016, 03:26:32 am
content: Don't worry, I've seen that here in Australia - but without audible feedback you would see it a lot more.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: November 11, 2016, 03:32:28 am
content: The problem is that a lot of the sound energy from the clickers is at higher frequencies, where hearing loss gets more common with age. At my age I can barely hear the audible part when driving at low speed, not at all at highway speeds.Classic case of not taking all human factors into account. It is further accentuated in my case since from my sitting position I can't normally see the visual indicators either. That is one reason some car manufacturers have made the front signal visible from the drivers position.

author: NottheDan
author_rank: Frequent Contributor
timestamp: November 11, 2016, 04:50:13 am
content: Quote from: CatalinaWOW on November 11, 2016, 03:32:28 amHow does that work? They are usually in the centre of the dashboard and if you can't see the dashboard something's wrong with your sitting position.

author: Brumby
author_rank: Unknown
timestamp: November 11, 2016, 05:23:00 am
content: I've noticed in some vehicles they are slightly recessed which will restrict the viewing angle.Remember, a lot of ergonomic decisions are derived from an 'average' person - and there are some people less average than others.

author: Cliff Matthews
author_rank: Unknown
timestamp: November 11, 2016, 12:26:47 pm
content: Quote from: NottheDan on November 11, 2016, 04:50:13 amCentre of the dash? Maybe yes, in a Mini or in the old dart, but cars from NA and Japan put most everything but the climate controls in one big molded plastic "pod" just behind the steering wheel. Maybe it's so the dealers can charge us more for repair..With so much tech advancement elsewhere, one would think ergonomics could get some priority, but maybe radical ergonomics would cause accidents. The HUD seems like a great idea for the Corvette, so why didn't they expand that? Could it be that Insurance Companies might charge buyers higher premiums on big changes?

author: Cliff Matthews
author_rank: Unknown
timestamp: November 11, 2016, 12:44:46 pm
content: I owned a 2000 Dodge Caravan and it had all the idiot lights up on top. It was rare to leave the turn signal on (confusing other drivers).This is one thing I wish my 2008 Caravan had.. and they call that progress?

author: Zero999
author_rank: Super Contributor
timestamp: November 11, 2016, 01:23:13 pm
content: Quote from: Brumby on November 09, 2016, 02:05:08 pmSimple. On modern cars, with an electronic flasher, a small speaker is used to generate the click noise. It shouldn't be difficult to add a speaker to your own design.

author: NottheDan
author_rank: Frequent Contributor
timestamp: November 11, 2016, 07:01:23 pm
content: Quote from: Cliff Matthews on November 11, 2016, 12:26:47 pmThat is the dashboard. The part that faces the driver. I'm not talking about those cars who have their instrument pods above the centre console but with the instrument panel behind the wheel. If you can't that then you have chosen a wrong seating position or a really really unsuitable car. So for someone to go "Oh, I never see that." ... That's somewhat worrisome.

author: SeanB
author_rank: Super Contributor
timestamp: November 11, 2016, 07:20:39 pm
content: Shoot, here using indicators would be a luxury, most vehicles rarely have working lights at all, you often see a vehicle driving at night with the only working light being one headlamp, possibly even aimed at the road.I did call the RTI one evening to report a HGV driving without any lights at all, aside from some very dim working emergency lights. They pulled him over, fined for the non working lights, and also found the vehicle was otherwise not roadworthy and overloaded. Helps to have the direct number for the control room, and they tend to want to keep these moving wrecks off the road, so they do not have to clean up the aftermath.As to panel design, often the function is overruled by appearance, so you might have lamps that are obscured by the steering wheel at times, or are not easily visible, or are just plain too small, to fit in the style. Like using a 2mm diameter red LED as an engine temperature warning light, and a 15mm blue LED as a bright beam indicator, right next to each other. Then run the red LED at glowworm level, and the blue at laser light level. Gauges that are tiny, and obscured by most driving positions. Then add a display that tells you all sorts of things, like the fuel range, transmission settings, mirror positions, seat positions, but that does not tell you coolant level is low when driving, or that the engine is approaching nuclear meltdown because the radiator hose ( which was recalled 6 months before, but the dealership did not do, despite having the vehicle in at least a dozen times in the interim, and having the hoses in stock for this) was known to break at the engine side.

author: Delta
author_rank: Super Contributor
timestamp: November 11, 2016, 07:34:38 pm
content: Quote from: Cliff Matthews on November 11, 2016, 12:44:46 pmWhat kind of maniac takes a photo whilst driving at nearly 70MPH, with the poor engine massively overheated, with low oil pressure, screaming at 5000RPM!

author: Zero999
author_rank: Super Contributor
timestamp: November 11, 2016, 09:05:39 pm
content: Quote from: Seekonk on November 10, 2016, 11:27:53 amSimulating it in LTSpice seems to suggest it will work with LEDs. One thing which will make it better at lower voltages is to use a logic level MOSFET, which will have a low enough threshold to turn on, but it would be advisable to protect the gate with a 15V transient suppressor diode.

author: Delta
author_rank: Super Contributor
timestamp: November 11, 2016, 09:10:34 pm
content: Quote from: zetharx on November 05, 2016, 03:53:07 pmJust use a proper incandescent bulb, instead of some daft LED thing...

author: Cliff Matthews
author_rank: Unknown
timestamp: November 11, 2016, 10:07:32 pm
content: Quote from: Delta on November 11, 2016, 07:34:38 pmHa! not my pic but funny. Now I recall each time it started, it did some kind of impressive self-check with all the needles cranked.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: November 12, 2016, 06:02:56 am
content: Quote from: NottheDan on November 11, 2016, 07:01:23 pmTry being over 2 meters tall. Steering wheel has to be tilted up to clear legs. Upper rim of steering wheel blocks much of the dash. I actually use a GPS unit sitting on top of dash to monitor speed. It is more accurate and easier for me to see than the speedometer.Of far greater concern than not being able to easily see the turn signal indicator lights is that the rear view mirror generally blocks vision out the right front quadrant of the car (LH drive here in the US). I have trained myself to crane my head around frequently to cover this blind spot, but it is less than optimal.I understand that I am way out on the tail of the distribution, so don't expect to have my every foible catered to, but I am sure that there are a great many people of various sizes and shapes that find one or more instruments obscured by the steering wheel, the instrument shade or other things. Or view of the road in one or more directions. It is a tough job to engineer for an operator who may vary from 1.4- meters to 2.0+ meters, with variations on how that height is distributed between legs and torso. Variations in arm length and weight from something like 40 kg up to well over 300 kg. All on a tight budget and while meeting crash test safety requirements. I am surprised they do as well as they do.

author: Delta
author_rank: Super Contributor
timestamp: November 12, 2016, 11:55:17 am
content: Quote from: CatalinaWOW on November 12, 2016, 06:02:56 am

author: NottheDan
author_rank: Frequent Contributor
timestamp: November 12, 2016, 12:07:53 pm
content: Quote from: Delta on November 12, 2016, 11:55:17 amI was more reminded of Bob Parr.

author: Brumby
author_rank: Unknown
timestamp: November 12, 2016, 01:51:17 pm
content: I was thinking of Jeremy Clarkson...

author: SeanB
author_rank: Super Contributor
timestamp: November 12, 2016, 01:52:58 pm
content: Reminds me of my high school English teacher, who hod to stoop to get through a standard doorway as he was 1.9m tall. He drove an original Mini, and simply removed the front seat and used the rear one, and for comfort opened the sunroof.But, between him and the other english teacher, who drove a Pallas, they fitted an entire class of the boarders into those 2 vehicles to go to an outing a few times. Made sardine cans look roomy, and they had to have 3 people to change gear and use indicators, but it worked. Between the 2 classes there were 11 boarders.

author: Brumby
author_rank: Unknown
timestamp: November 12, 2016, 01:53:55 pm
content: Quote from: SeanB on November 12, 2016, 01:52:58 pm.... like officer Hightower:

author: Brumby
author_rank: Unknown
timestamp: November 12, 2016, 01:59:53 pm
content: Quote from: CatalinaWOW on November 12, 2016, 06:02:56 am(I hope I haven't offended.)

author: SeanB
author_rank: Super Contributor
timestamp: November 12, 2016, 02:12:14 pm
content: My mother drove a VW beetle for years, and she was very short. To solve the problem of the feet not meeting the pedals, my dad simply moved the seat mounts forward around 20cm, using a block of wood and new holes ( with appropriate steel bracing under the pan to spread the load to the chassis) for the seat mounts, so he could also drive the car by moving the seat all the way back. then, to see out the windscreen, mom simply used a big firm foam cushion to lift her above the steering wheel, while still touching the pedals.Later on she changed to a Renault 5, and this car suited her perfectly, even if she did drive for over a year on a single tank of fuel, and it had a rattle my dad could never locate, even after he had the entire interior and dashboard of the car, aside from the crate he was sitting on to drive, sitting in the garage. that did annoy him, as he was an automotive engineer, and should have been able to find such a small thing. Eventually he took it as the actual metalwork simply having a resonance at certain speeds.

author: CatalinaWOW
author_rank: Super Contributor
timestamp: November 12, 2016, 04:03:20 pm
content: I have taken no offense at any of this. I actually drive a pretty large vehicle, a Chevy Tahoe, which still is in some ways not large enough. Strangely there have been a few vehicles that do fit, but they have been outside my financial reach. The 1950s Studebaker Hawk. The 1970s Jensen Interceptor III. And the current Tesla Model X.