Fredmahan

So I was able to get a used OEM 1992-94 flasher relay and install it in the 1993 SC300. When I turn on the R or L turn signal, the lights on that side come on, but don't flash. When I depress the 4-way flasher button, all 4 lights come on but don't flash. I removed the relay and put in a different one. It caused the lights to act in the same way. I checked the colored blade fuses (but not the little aluminum box fuses) and they looked okay.
Any ideas out there?
Fred

KahnBB6

iTrader: (5)

Hmm. Two used relays causing the same condition? Hold onto both of them as it is unlikely that both would have the same exact issue and before this your original flasher relay allowed one signal to flash but not the other. We'll have to consult the SC300/400 Toubleshooting TSRM for this circuit.

CaptSal

Were is the Turn Signal Flasher located on the SC400

KahnBB6

iTrader: (5)

On 1992-1994 SC300/400's (and 1991-1994 Z30 Soarers) it is a large and unusual looking blocky relay located in the driver's side kick panel area. You actually need to pull the carpet up just a bit in order to access it. There is a catch on the rear side that holds it in which you must gently and carefully get to un-latch before it will come out.

See these pictures below for a visual reference of the SC's driver side kick panel fuse and relay block out of the car:






These model years have very over-designed relays which actually contain two relays inside them. Toyota's engineers deemed this necessary at the time to better spread out electrical load and stress but they simplified it for 1995 model years and newer. It uses a standard 5-pin Bosch relay as a physical interface into the car but that's where the similarities end since those pins on the 02-94 OEM flasher relay don't conform at all to the functions of a common 5-pin Bosch relay. It is all very proprietary Toyota inside.

On 1995-2000 SC300/400's (and the same model year Z30 Soarers) the signal flasher relay is a much different and more conventional design in the same location.

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If you are having trouble with a 1992-1994 SC300/400 signal flasher relay please refer to this thread where much research and more than one solution has been found:
https://www.clublexus.com/forums/per...0-24020-a.html

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Unfortunately the 92-94 turn signal flasher relay is no longer made or sold by Toyota/Lexus and there is no easy off the shelf aftermarket equivalent flasher relay that can replace it (believe me, I tried as have others).

HOWEVER! I strongly, highly recommend you KEEP your original 92-94 turn signal flasher relay and have it sent to an electronics specialist who can replace the capacitors and possibly any simple and easy to replace resistors with the exact values and brand components in order to resurrect it (you or the repair service can buy these electronics components from a reputable supplier such as Mouser or Digi-Key).

This has already proved successful for a couple of 92-94 SC owners and should be just as applicable for early 91-94 Soarers.

Please, please, please DO NOT throw away a malfunctioning 92-94 SC (or 91-94 Soarer) signal flasher relay. If you are using a mechanic for your repairs do not let them throw away this part either! Chances are it can probably be repaired and restored to full working condition! It is a very unique design, technically built to last and given that they aren't sold or made any longer it is best to try for a reconditioning repair first before doing anything else.

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Now, I mentioned that thread link above which goes very in-depth into the 92-94 SC and 91-94 Soarer flasher relay design and potential alternatives. CL member Lex2k actually did come up with a clever prototype relay replacement for 92-94 models. He used a generation 5 Camry OEM flasher relay but with some modifications to its harness on the end with a cannibalized Bosch 5-pin relay to emulate the specific functions of the 92-94 SC flasher relay. His design is LED capable and probably is better to run with LED bulbs to lessen the overall wattage load on the new relay. It hasn't been tested for long term reliability yet on many 92-94 SC's but it works and is a good alternative. Tail light failure warning ECU would need to be disabled with the use of LED bulbs, btw.

First I would still recommend getting your 92-94 signal flasher relay repaired with new capacitors and resistors. If that doesn't work out, then look into Lex2k's solution. Or... if you are dead set on converting all your signal bulbs to LEDs then his flasher relay solution for a 92-94 is also worth considering.

However no matter what you do I strongly recommend keeping your original 92-94 SC signal flasher relay. Do not discard it. Keep it with your SC's spare parts. Usually it can be repaired and put back into service.

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If you have a 1995-2000 SC your turn signal flasher relay will be much easier to replace if it has gone bad since it uses a much more conventional design and is still available new from Toyota/Lexus as of this posting.