Thanks John. I've just found out this weekend that my modded rear turn signals stay lit amber if the auto headlights are on and it is daytime! So much for the hours of work I put into the turn signal mod. But, your off-delay relays are the answer to my issue and will also allow me to use switchback bulbs on the front turn signals so that I both solve the rear turn signals and get white DRLs.
DRL on a Solstice 2006 base
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An update on this. I've ordered on-delay relays (not the ones suggested above because those are not available in Brazil) and since they are not weatherproof decided to install them inside the car on the BCM area.
I found out that John's suggestion works but there are a couple caveats I still have to tackle. One of them related to how the BCM works, and the other due to how the relays I got work -- might not be a problem for other brands/types of relay.
The 1st issue is that when the BCM commands the turn signals "constant-on" (ie. DRL mode) it expects there to be a current draw from the bulbs. After installing the relay to switch the DRLs off, the BCM will presume bulbs are burned and when you use your turn signals you will get hyperflass, as if both bulbs were burnt. In my case due to the way my relays behave, hyperflash is quick enough for there to be no time for the relays to turn off, so the BCM never senses a load and keeps flashing quickly. I'll try to fix this by wiring the NO contact or the relays to the "white" pin of my switchback turn signal bulbs so that I get white DRLs and the BCM sees a load.
The second issue has to do with my relays. The type of circuit they use is not suited to quick switching. Timing seems to be related to a capacitor and how quickly it charges/discharges. So what happens is with time the capacitor picks up a "residual charge" from the on-off pulses of the turn signal wires since it charges a little, then discharges but always less than what it had charged, and reaches a point where the relays start to buzz in a almost-latching situation. They would also flutter when turning on, this was fixed by changing the caps from 100uF to 47uF ones I had lying around. There seems to be a discharge resistor ( I measured 64 kohms between the capacitor pins when I had removed the 100uF cap) in the circuit and maybe I could change its value to allow the capacitor to discharge more quickly?
Here's a couple pics of the relays ready in the box I mounted (hot-melt-glued them actually) on to.
Can the resident electronics wizards help me out put maybe? Calling @TomatoSoup, @JohnWR, @kgschlosser... Thanks
I found out that John's suggestion works but there are a couple caveats I still have to tackle. One of them related to how the BCM works, and the other due to how the relays I got work -- might not be a problem for other brands/types of relay.
The 1st issue is that when the BCM commands the turn signals "constant-on" (ie. DRL mode) it expects there to be a current draw from the bulbs. After installing the relay to switch the DRLs off, the BCM will presume bulbs are burned and when you use your turn signals you will get hyperflass, as if both bulbs were burnt. In my case due to the way my relays behave, hyperflash is quick enough for there to be no time for the relays to turn off, so the BCM never senses a load and keeps flashing quickly. I'll try to fix this by wiring the NO contact or the relays to the "white" pin of my switchback turn signal bulbs so that I get white DRLs and the BCM sees a load.
The second issue has to do with my relays. The type of circuit they use is not suited to quick switching. Timing seems to be related to a capacitor and how quickly it charges/discharges. So what happens is with time the capacitor picks up a "residual charge" from the on-off pulses of the turn signal wires since it charges a little, then discharges but always less than what it had charged, and reaches a point where the relays start to buzz in a almost-latching situation. They would also flutter when turning on, this was fixed by changing the caps from 100uF to 47uF ones I had lying around. There seems to be a discharge resistor ( I measured 64 kohms between the capacitor pins when I had removed the 100uF cap) in the circuit and maybe I could change its value to allow the capacitor to discharge more quickly?
Here's a couple pics of the relays ready in the box I mounted (hot-melt-glued them actually) on to.
Can the resident electronics wizards help me out put maybe? Calling @TomatoSoup, @JohnWR, @kgschlosser... Thanks
Attachments
Quick googling found me this. Maybe the BCM never zeroes the input when blinking since with filament bulbs it's not an issue?
Attachments
I've added a pair of 15ohm/10w resistors in parallel (effective values combined 7.5phm/20w). It did solve the hyperflash (as predicted) but not the relay's unstable operation (as hoped).
photos.app.goo.gl
I'm pondering whether there would be a way of discharging the timed relays' capacitors more quickly. Otherwise maybe the best solution is a microcontroller such as used by @TomatoSoup on the Kappablinker.
New video by Anderson Perazzoli
photos.app.goo.gl
I'm pondering whether there would be a way of discharging the timed relays' capacitors more quickly. Otherwise maybe the best solution is a microcontroller such as used by @TomatoSoup on the Kappablinker.
Sorry, I've been travelling down to Florida (mother-in-law checkup) so missed your reply before. Hmm, I now fully understand the issue. I'm making assumptions here as it's a bit difficult to debug without knowing what the exact circuit layout is, but I see from your pics that your relay boards are using a 555 timer chip. Problem is the standard "delay on" circuit for this is really not meant to do what you want it to do. It doesn't expect to have continual on-off power and there is no discharge of the timing capacitor except for through the same resistor used to charge it in the first place, so the result is exactly what you've found. Offhand I'm not sure there's a way to fix this with your boards.
If I were doing this, I'd do it as you suggested earlier, with a microcontroller.
If I were doing this, I'd do it as you suggested earlier, with a microcontroller.
Thanks, you know what I thought: maybe a transistor could be used to alter the charge/discharge path for the circuit? When powered the transistor switches the path to include the delay resistor. When not powered the path switches to a smaller resistance resistor that will allow a faster, or instant discharge.Sorry, I've been travelling down to Florida (mother-in-law checkup) so missed your reply before. Hmm, I now fully understand the issue. I'm making assumptions here as it's a bit difficult to debug without knowing what the exact circuit layout is, but I see from your pics that your relay boards are using a 555 timer chip. Problem is the standard "delay on" circuit for this is really not meant to do what you want it to do. It doesn't expect to have continual on-off power and there is no discharge of the timing capacitor except for through the same resistor used to charge it in the first place, so the result is exactly what you've found. Offhand I'm not sure there's a way to fix this with your boards.
If I were doing this, I'd do it as you suggested earlier, with a microcontroller.
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