use only the correct parts for this or fail you will, guessing does no work in electronics ever, (or engine or trans)
so cant find it at rockauto first. always look there as they have deep support for sure relic cars, not seen on the road now,(rare)
and deeper choice of all parts for this car, huge choices
even top brand. (but this case, too rare)
not sure me your question, at all, now to test electrics on cars or what/? as in using a voltmeter to find what is bad,
check fuses first.
33 years old is not any kind of spring chicken,. car it is super old.
means parts now hard to find, I'd sell it as a classic. me.
my fav year for cars is
1996, (just one computer to make happy)
USA answers all, no where else me.
your car parts sellers all ask this first
DLX All Trac; DLX Model; LE All Trac; LE Model; w/ Cruise Control
try here first
https://www.rockauto.com/en/catalog/toyota,1989,camry,2.0l+l4,1272899,electrical-switch+&+relay,turn+signal+relay,3904
even find it there then google it find it closer to secret country
learn to google for sure and 10x that rare 33 year cars.
or ask the toyota dealer for parts?, expect laughs or silence