So about a couple months ago, my overdrive indicator started occasionally going dim. Everything seems to be working, but dim light has been on more often than not recently. Not sure whats going on here and was wondering if anyone else here has experienced this issue?

Thanks

 

is this light coming on dim when the OD is enabled (and the light should be off) or when the OD is disabled (and the light should be on) ?

the light is wired between the output of the OD relay and pin 15R of the ignition switch (hot in RUN (II) and START (III)). This same 15R connection powers most all the lights on the dash, so if the rest of your lights are OK, thats likely NOT the problem.

the OD actuator solenoid is wired between that same output and ground, so the solenoid is ON when the light is OFF and visa versa.

My guess is bad connections on the OD light, or solenoid or dashboard connections or wire between them.

the relay output on pin 87A goes to a yellow-red wire through a couple connectors to the dashboard on pin 34 (a single pin connector at the lower right corner of the back of the dashboard, right next to the OD light). the relay output is ALSO on pin 87, which goes to a white wire to the actual OD solenoid (pins 87 and 87a are connected inside the relay).

hope that helps. if you can answer my first question, I could make some random guesses at possible causes for this. it might just be a crappy bulb thats about to die, or a bad connection of the bulb socket. each of those indicator bulbs is in a little plastic socket that fits into the back of the instrument panel. a bit of Caig DeoxIT on the contacts would be a very good thing.

 

The light is dim when overdrive is on, and of course bright when it is off. Sometimes after I click the button on and off a few times the light will no longer be dimmed, or if I've been driving a while.

Thanks for the response!

 

ok, so if the light isn't shutting off entirely, maybe there's some leakage current.

could be the relay? the relay powers pins 67 and 67a when the OD is enabled, and grounds it when the OD is disabled. if the relay went 'open', then the light would ground through the solenoid which would result in a dim light (and a partially powered solenoid).

 

I was kind of leaning that way with the relay, I'll check it out.

thanks!