*** fc OVER CHARGING - 16 VOLTS where is the alternator relay located?***
 

my uk rx7 fc turbo vert is over charging at about 16.1 volts and also my battery warning light is not comeing on:icon_tdow

iv replaced the alternator aND BATTERY still the same

i belive my relay may be fuberd but im not sure where it is

any help:icon_tup:

cheers

i believe its an s5

two wires on the alt are blue and white and black and white which goes to the warning light i believe

Not sure what relay you're referring to but the charging current is regulated in the alternator anyway, not at a relay.
If you're overcharging, you have a bad alternator.

did you verify this with a multimeter and not the guage? reason I ask is my gauge wigged out one day and reads 16 volts whnenits really just at 14

and yes the alternator is internally regulated, so you would need a new alternator if this is the case

i had a loose connection at the alt once and it gave me 17 measured volts. sucker was crankin...

check those connections real fast. unplug and plug back in harder.

If you are referring to the alternator warning light relay then it is located in the idiot light box on an S5 and the wire color should be White/Black.

cheers guys yea the relay for the warning lamp

eeeer what is the idiot box I feel im being an idiot not knowing what it means lol

The unit which has the digital clock plus all the warning lights.

check the voltage at the battery with a voltmeter, never trust the interior gauges to always be correct.

check connections at the alternator and the battery voltage with the car off, the battery should be at roughly 12.6v static. if it's reading below 11v then you may have a faulty cell in the battery which can cause overcharging.

if you had the alternator repaired/rebuilt, then it likely wasn't tested properly while spun up to speed and the regulator is faulty, in which case replace the alternator.

You most likely have a problem with the sense wire as I believe around 17V is basically unregulated max power.

The alternator is looking for "Feedback" to determine proper voltage. A quick test would be to jumper a wire from the alternator output to the sense wire input. This should drop it to 13 ish volts as you will have almost 0 voltage drop.

I put an FD alternator in mine, battery in the back and with all the new wire was seeing only 13.5 V at the battery when Hot. I wanted to get up around 14.5 to make sure the fuel pump was getting enough juice so I added a diode to the sense wire to trick it into thinking the voltage was ~1 V less than it really was. Check out my post here as it seems a lot like the issue you are having (except you do not have the voltage drop my system had)

https://www.rx7club.com/2nd-generati...lights-966168/

cheers guys iv got another alternator on order, as I found the bat warning light bulb blown, replaced and still charging at over 16 volts :( so hopefully the new alt does the tric

I've had over charging due to a bad battery once before. My radio quick working because the alternator was supplying too many volts.

replace your battery as well, overcharged batteries pop quickly and leak sulfuric acid.

yet another new alternator with new alt warning bulb and is now charging ok will re chaeck over the weekend

cheers for the replys