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Turn signal indicators flash rapidly on dash. Both front turn signals (and hazard) not working, bulbs appear to be good. Rear turns signals (and hazard) work as should.
I read some of the threads here but I'm still a little uncertain. I suspect bad flasher relay. In photo attached is that green component the flasher relay? It's right by the clutch pedal arm. When I activate the turn signals it's very hard to determine if the sound is coming from that or not. I can grasp it between my fingers but I cannot feel it doing anything when turn signals on.
So - Is that green component the flasher, is it reasonable to suspect it's bad and any reason to get the $50+ replacement versus the $13 on from autozone?
Why would you suspect the flasher, as opposed to, say, the alternator? You have one flasher for all turn signals and hazards. Half of those are working correctly. Why would the flasher flash the rears but not the fronts?
Rapid flashing "means" you have a bulb out (or a broken wire ...). Bulbs that "appear" to be good might not be. You can swap them front to rear, but the smart way to check them is with a multimeter. My EWD shows the wiring to the fronts is spliced directly to the rears; if you have an "open" to ground on the center pin of the socket, you probably have a broken wire somewhere. (Since both of your fronts are out, you could have a bad ground, I would also check for continuity to battery negative from the socket body.)
FWIW, "Standard Motor Products" from Parts Geek is no more OEM than Dorman. This is the OEM part: https://parts.lakelandtoyota.com/p/t...198032010.html But there isn't much to a flasher; if you really want to use the Parts Cannon I'm sure the $12 one will work just fine.
There are alot of parts for these trucks where I would say OEM is the only way to go if you can get it, flasher relays is not one of them. As scope said, I would suspect a burnt out bulb or short to ground somewhere first though.
I guess I suspect the flasher cause I hoped it would be something as simple as that + I am a rookie at most level of car electric diagnosis. Also, even though I was not thinking alternator but understand now that could be a cause, in my case I had alternator rebuild by pro shop about 10k miles or more ago.
I have a multii meter but I’m not sure how to test a bulb with it, or how to specifically check ground and continuity at the two places you recommended. I am keen to know how to do this and confident I can do it without much trouble. I will look into how to do these tests.
...I guess I suspect the flasher cause I hoped it would be something as simple as that ...
...I have a multii meter but I’m not sure how to test a bulb with it,...
Toyota components are very reliable. Suspect connections first.
More important than the multi-meter are our senses. See, feel, hear, smell corrosion, loose contact, overheated contacts (yes they smell burnt) from arcing, etc.
On the the other hand, a burnt bulb may look OK, so you need to look much closer or use your multi-meter. Lots of simple instructions on youtube.
Rapid flashing means flasher sees high resistance. It could be from busted bulbs, broken wires, corroded contacts, etc all of which produce high resistance.
Last edited by RAD4Runner; 06-03-2021 at 08:10 PM.
OK I'm going to test the bulbs first. I had taken both lenses off and inspected bulbs and connectors. The bulbs look good, the connectors look good. No signs of corrosion or smell or signs of any arcing, it all looks, sounds and smells generally OK.
Your multimeter will certainly have a resistance (ohms) setting. It might have a "continuity" setting, where it beeps on (what it considers) a short.
Pick the lowest ohms range you have (probably 200 ohms). Touch the probes together; it should read something less than 2 ohms (technically, it should read zero, but the leads have some resistance). Take them apart; the meter will read something like "0L" (which means the resistance is higher than your 200 ohms max; which makes sense, because when the leads don't touch the resistance is pretty much infinite).
Touch the terminals on your bulb. If you get "infinite," the bulb is burned out. Anything else (probably around 20 ohms) is okay.
Getting the hang of it?
PS I was kidding about the alternator. You have one alternator; how could any problem with the alternator only affect half of your turn signals?
1989 4x4 Pickup, 22RE, 5 speed manual, @180K
Original Owner"
BTW, good job indicating model-year-engine-transmission.
That info often saves everybody time.
Schematic below is for 1988 but may be similar to yours...
Photos show a little corrosion on bulb base. I cleaned that off and also scratched up the contact inside the bulb housing.
I set my multi meter to 200 ohm. turn on and it reads Infinity, touch probes together and it read 0.9. Put one probe on the bottom center of bulb base and the other probe on the little solder spot where the metal base and glass meet and it reads 1.0 - 0.9 (did this on both bulbs and got the same). so not reading 20 ohm, but I think the bulbs are good?
When I put the bulb in the socket and then put the multi meter probes on the two connector pins (white arrow in photo) the meter reads Infinity. this is the same for both turn signal housing/bulb. Not sure if this indicates anything?
Originally Posted by scope103
if you have an "open" to ground on the center pin of the socket, you probably have a broken wire somewhere. (Since both of your fronts are out, you could have a bad ground, I would also check for continuity to battery negative from the socket body.)
I am not sure how to go about checking the things quoted above? Not clear on where the "center pin of the socket" is and how to check it for ground? Also not clear on how to check for continuity to battery negative from the socket body?
I do have a couple of pieces of 14guage wire with alligator clips on each end. Am I correct that if I attached one of those to each pin on the back of the bulb housing (white arrow in photo) and then connected the other ends to 12 v battery terminals then the light bulb should light up?
Thanks again for your help and please forgive my very limited understanding and knowledge of using a multi meter for this testing.
Thanks again for your help and please forgive my very limited understanding and knowledge of using a multi meter for this testing
RAD: That's what yota bros are for. We are happy to help those who help themselves.
1.0 - 0.9 (did this on both bulbs and got the same). so not reading 20 ohm, but I think the bulbs are good? RAD: Around 1 ohm is typical.
...When I put the bulb in the socket and then put the multi meter probes on the two connector pins (white arrow in photo) the meter reads Infinity. this is the same for both turn signal housing/bulb. Not sure if this indicates anything? RAD: Contacts not clean enough or not making tight contact. Wondering about the odds of both assemblies going bad at the same time, tho.
Also not clear on how to check for continuity to battery negative from the socket body? RAD: Pls post picture of pins in harness side of connector.
if I attached one of those to each pin on the back of the bulb housing (white arrow in photo) and then connected the other ends to 12 v battery terminals then the light bulb should light up? RAD: IF bulbs are good and contact are good and tight, Correct. Make sure the clips do not touch each other, or else... LOL!
OK. They appeared to be clean but hard to really see so I scraped away at those small contacts (white arrow indicated) with the tip of a sharp knife. Then the ohm reading got to be more like 2.0 - 1.5. Put all back together and....the turn signals now work!
Very grateful for your help, and so are the other drivers on the road who now know when I plan to turn, change lanes or etc.
OK. They appeared to be clean but hard to really see so I scraped away at those small contacts (white arrow indicated) with the tip of a sharp knife. Then the ohm reading got to be more like 2.0 - 1.5. Put all back together and....the turn signals now work!
Very grateful for your help, and so are the other drivers on the road who now know when I plan to turn, change lanes or etc.
Thanks!
Sweet! Happy to help. Cost less than the flasher, eh?
Yeah corrosion could be hard to see. That's why we gotta look closer. See how you doing your troubleshooting methodically, your sense of vision combined with the humble multi-meter solved it?
Best to apply 100% silicone dielectric grease (like Permatex brand) or "bulb" grease on contacts to help prevent further oxidation.
For light corrosion build up, quite often you need nothing more than a pencil's eraser. Just "erase" the contacts until they're nice and shiney.
For heavier corrosion that needs more than a pencil eraser, a typewriter (remember those??) eraser will do the trick. One of the ones that's white, not pink like on the pencils.
Either way, definitely use the silicone dielectric grease on the contacts in the socket. I put a dab into every plug I take apart before I put it back together. Not only is it great for keeping the contacts in a plug nice and clean and corrosion free, but it also works great on rubber o-rings. Heck, anything made of rubber. I use the silicone dielectric grease for the little rubber items, and Vaseline on the larger ones. Like the rubber door seals, window seals, and so forth. The rubber door and window seals on my 87's are still in good shape, as I hit them every fall. It really works well for keeping the doors from freezing shut on those really cold mornings.
Thanks Pat! Great tips. I will try the eraser and I will get a tube of dielectric grease. Also will try the vaseline cause my door seals freeze up on cold mornings 4 sure. Truck lives outside at 9,000'
I learned some more about using multi meter and I hope to learn more about basic testing procedures for proper ground, broken wires etc.
Like Rad mentioned, one of the best trouble shooting tools is the Mk I eyeball. Even for grounds. LOOK at both ends. Any corrosion, dirt, or grease on the ring terminals where they bolt to whatever. Usually the body. Again, use your pencil eraser, until the metal of the terminal, and the body it bolts to are nice and clean. A little dab of dielectric grease, and you're good to go. Same for the male contacts in a plug. A few passes with the eraser, grease, done.
Just a hint, the plugs that go on the back of the headlight bulbs develop corrosion pretty badly. If your bored someday, pull them off, hit the male pins on the bulbs with the eraser, a little dielectric grease in the femaless, and they'll stay in good shape longer.
Alternatively, measure the resistance to the battery's negative terminal. It should be 1 ohm or lower. Preferably MUCH lower. Any higher, take it apart and clean it up real well.
Remember to pull the leads off the battery itself before you ohm ANYthing out. Just a tiny amount of voltage into the meter in ohms mode will destroy the ohms part of the meter very quickly. Many have fuses these days. If something like that happens, check the meter's manual for if it has a fuse, and if so, where, and what amperage rating it has.
I'm glad for your door seals. Give them a good dose of Vaseline in the fall. It gives some of it a chance to soak into the rubber, preserving it. I'm only at 4500 feet, but we've had some real cold, snowy, mornings. I was glad I had Vaselined my door seals, I can tell you that! Very handy that some very inexpensive "stuff" can prevent aggravation, and preserve the rubber so nicely.
Have fun, and if you have more questions, feel free to ask. The only dumb question etc...
Pat☺
06-03-2021, 01:47 PM
