98 s70: LED hyperflash

Post by **CIK7** » 08 May 2021, 14:40

I bought amber LED bulbs for the front and back. Now I am experiencing hyperflash due to low power usage. Also the front ones dont flash. Is this due to extremely low power usage? I found out I could buy an LED relay, which I did based on entering my car info. I cant figure out which relay is for the front turn signals. Im excited to get this done. By the way, searching the P80 forum brought no results for hyperflash. Who else has experienced this issue?

Azik09 · Post by **Azik09** » 09 May 2021, 06:02

CIK7 wrote: ↑08 May 2021, 14:40 Also the front ones dont flash. Is this due to extremely low power usage?

Yes.
Flasher relay is incorporated in hazard lamps switch. So you have two ways to solve the problem:
1. Add ballast resistors in parallel to LED lamps. 10Ohms or less, try by experience.
2. Disassemble hazard switch, find a current sense resistor and increase its resistance, by experience too.

Post by **scot850** » 09 May 2021, 15:06

Our friend Azik is a wise man.

A buddy just did the same thing on his 99 Toyota Taco. Really fast turn signals. He changed the relay to fix. Only in his case that wasn't the only issue. He also had bad earths as well as a bad turn signal switch. Cleaning all the above helped as well.

With Volvos they also have the bulb check circuit that flashes a warning light when a bulb is used when out. The resistance you add in may have to compensate enough to trick the system to ignore the LED bulbs. I am no expert on the electrics side of things but know enough to be dangerous!!

Neil.

Post by **abscate** » 10 May 2021, 07:37

It’s a classic case of adding new technology to a system that creates more trouble than it was worth.

Post by **CIK7** » 10 May 2021, 19:49

abscate wrote: ↑10 May 2021, 07:37 It’s a classic case of adding new technology to a system that creates more trouble than it was worth.

Im bound to succeed. Resistors are on the way. Also about to post another on 'what did you do to your volvo today?'