issue is on my 1987 4runner 22re

im having a small annoyance with my volt meter, and although it doesn't effect the performance of the truck I want to try and resolve this. when my turn signals are used, my volt meter moves with the flashing of the lamp. I have a BRAND new oem Toyota alternator that is good. I do have a multimeter but im not really sure where to check to see whats going on. I have been going through some forums on here and mud, and I did see a few people mention that the flasher could be causing the issue. a new flasher is about 50 bucks from Toyota, I know they are cheaper at vatozone but im a princess about my parts on this truck and prefer oem. I will admit 50 bucks for a flasher seems ridiculous. has anyone else had this issue that has successfully resolved it? the other threads I found weren't followed up on so if the OP solved it they didn't say. im far from proficient on a multimeter but I can get where I need to with a little guidance. thanks.

 

I guess I don’t fully understand what you’re trying to “fix.” The voltage drop across the cluster when the turn signal blinks? Or a voltage/charging issue you’re having?

Check voltage at battery with engine off. Start engine. Check voltage at battery with engine running. With engine running, turn on hazards or turn signal in one direction or the other and check voltage at battery.

If voltage at the battery does fluctuate with the blinkers then there’s an issue. Check relay, fuse, fuse block, wiring.

I’d wager you won’t see a drop at the battery, because the voltage drop is at/across the gauge cluster. Therefore nothing needs fixed, unless you want change factory wiring.

 

the volt meter on the dash should not fluctuate with your turn signal, this is a recent development with my truck. there is no noticeable drop at my battery. like I said, I have found threads with people who have the same issue, one guy ended up have a bad alternator but mine is good. I ordered a flasher already, mine is original so it wont hurt to replace it.

 

Do you have a fsm? Look at the wiring diagrams.

The volt-meter and turn signals are at the end of a series of wired connections, some inside relays, others are inside switches, and share the same 15a ENGINE fuse for power, which is directly between the alternator and ignition switch. Ignition switch then connects to battery positive. The turn signal bulbs in the gauge cluster and the voltmeter get power from the same circuit and are grounded separately from each other. Clicking yet...? You’re connecting the power side of the turn signal circuit that shares the same power side of the voltmeter. You don’t see a fluctuation in the oil, water, or fuel gauges etc. because they are connected to variable resistors then to ground. (Not a voltmeter) The tach is unaffected because the diode above and the capacitor below.

Even if all wiring and connections are perfect, even off the lot NEW, you will see the voltmeter move an inaccurate amount because there is indeed a current draw on that same circuit. There is a negligible current draw at the source. (Battery/alternator)

As long as there is no drop or over charge condition at the battery to alternator connections, then there is no need to be concerned. It’s not the voltage regulator. If all turn signal and voltmeter grounds are clean and secure then that only leaves a high resistance connection somewhere (likely old wiring, corroded connections) that causes a voltage drop with the current draw from the blinkers. Jumper the blinker relay so that the bulbs stay on and check voltages.

Are YOU trying to figure out what’s wrong or just replacing parts, and asking someone else?

Does the voltmeter jump with the hazards turned on? It shouldn’t.