Daylight running LEDs (DRL) and indicator signals on Chrysler

This is a short post on fitting daylight running LEDs to my Chrysler Grand Voyager 2.8CRD. This should work with most editions of the GV, I'd expect right up to the newer facelift editions, so right through to 2007/2008 I believe.

So the first step is ordering the right DRLs, I went for ones that have DRL and indicator function built in, as some information suggests when indicators are on the DRL should switch off to avoid confusion to oncoming drivers, I also like this 'look' where the DRL goes off, the indicator flashes and when indicators are cancelled then the DRL will come back on. This needs units with a little electronics but you can buy these for around £10 easily in the UK. I went for the longer 60cm lights, and went with the light 'bar' type where the LEDs are inside a plastic diffuser to give a more even illumination.
The next job was how to connect into the indicators, I took the headlight unit out (3 flathead screws at the top of the headlight assembly), undid one bolt that holds the plastic facia of the bumper around them for easier access and the headlight comes out. Checking the connector I identified the wire and spliced a wire into it using push/crimp connectors.
That connection goes to the orange wire on the DRL for that side, you then run two other wires, one is ground to either the nearest grounding point, or a post on the battery terminal. The other needs to feed back to an ignition switched live, I went for in the fusebox a small piggy-back fuse splitter and connected this to the cigarette lighter/acc socket fuse. This allows the DRLs to be on whenever the ignition switch is on (Remember the DRLs are very low current draw).

Fitting them, I had the option of above or below the existing lamp, both are relatively easy, but to squash the led bar in nicely I went for underneath, which gives good results, the light actually shines a little through the existing lens so it partially lights the main light up in duller weather.

Results were good.
Here you can see the position of the LED tubes underneath the lens.

It took a little pushing/pulling to get in the right place, I'm not 100% happy as they're not even over the whole headlight lens but I'm going to fix that by moving them around and possibly using dots of superglue to hold them against the headlight.

These are pretty bright when on and give off a nice glow:

And when the indicator is on the white DRLs go out and replaced by a flashing (in time with your indicator flash) orange bar:

(Catching the flash was difficult, here you can see the 'off' part of the sequence, hence it's not as bright as it actually looks!)

All in all for £10 and an hours work it went really well!

12v LED indicator bulbs for Chrysler grand voyager

A short post this one, but I noticed the orange colour was fading from my rear indicators on my Chrysler Grand Voyager.

This is a common problem on many cars now, as they use clear lenses and an orange bulb to make the indicator orange. This 'solution' to me is flawed and since its the bulbs with an orange paint on them, over time the pain burns off/fades which is what happened with mine and the indicator now looks white rather than orange (This is an MOT fail here in the UK, and as my MOT is due I needed to sort it)

So I found these LEDs on an ebay listing

They are ORANGE 581 BAU15s PY21 replacement LED bulbs in the same package, etc.

One warning that I saw on the Chrysler Grand Voyager forums is that the voyagers electrical wiring is non-standard and actually has positive on the surround and negative on the central pin. On normal bulbs this isn't a problem as they don't care about polarity, but LED's require + and - polarity so this could have been an issue.

I did a test with my multimeter on the pins and verified that this was NOT the case though, the central pin was positive like on all other vehicles as standard, so first issue out of the way.

The bulbs fit into the holders fine, and then into the external bulb/reflectors fine too, so these are the right size and shape.

Testing them with the hazard indicators on, all looks good, swapped them and they were blinking away and brightness looked ok (I did expect a little brighter to be honest, but they were comparable to the existing ones).

So all was well.

Until the next day when I actually drove to work, and realised that when I put the indicators on I got the dreaded 'fast flash' or hyperflash as some people call it. This is where the indicator bulbs flash very quickly. Most cars were designed to have a load from the bulbs and this allowed them to flash at a normal pace. When a short or an open circuit (bulb failure) was detected, the current consumed dropped and this causes the flasher unit to flash faster, the idea being that it was then easy to tell when a bulb had failed and needed replacing.

Unfortunately the LEDs consume a lot less current than the original bulbs and so this was causing the circuit to think the bulb was missing, when in fact all the bulbs and LEDs were lighting up correctly.

Doing a bit of maths I can calculate the difference.

These are 24LED units, and assuming an LED voltage of 2v for orange and estimating at 25mA per LED, adding that up we get 0.05 watts at 2v per LED. Multiple by 24 and we get 1.2 watts in total.

The usual bulb consumes 21 watts, so there is a difference of 19.8 watts, which is quite significant and obviously what the car is detecting and causing the fast flash.

There is a solution, this is to use a load resistor. This is effectively a resistor across the terminals (shunting the voltage/power through the resistor as well as the LED) which causes a higher current to flow and the indicator circuit to think it has a valid bulb installed.

This has several problems for me, firstly it's a waste. We would be wasting current shunting it through a resistor effectively wasting this current through heating the resistor up. Secondly you have to cut into the wiring loom and install this load resistor which is untidy and messy. I'm also not sure if this will stop the bulb sensing for the other bulbs in the indicator circuit (I only swapped the rear to LED, front are still standard). So this to me isn't a good solution.

I still did the maths to calculate what resistor I'd need.

So for 19watts at 12v this is 1.58 amps.

So using Ohms law (V = ir) I could calculate the resistor size. So 12 = 1.58R, and calculating that it comes out at 8.2 Ω (Ohms)

So if I were to install a load resistor it would need to be an 8.2 Ohm 19 (or 20) watt resistor. (Which are the larger ceramic style rectangular units as they are dissipating so much wattage)

Therefore I'm thinking of swapping and going back to the regular bulbs rather than LEDs as don't think this solution is quite right. I'm open to comments though, please let me know your thoughts.