Icemark

Well yes of course it would show you voltage if you had it on the 12 volt setting.

It should have been on the amperage (amp) setting. To test for a draw you need to test in amps not in volts.

X-JaVeN-X

Alright, well my car is s4 all around...so assuming the wiring is correct as the car didn't have this problem earlier....what would suggest looking at first?

rurouni2071

alright , I cut the black/white wire and ran a 5A fused wire directly from the battery to the L terminal

still I get just under 12 volts , once after I revved it to 2500rpm it went up to 14v then it kicked down again and wouldnt go above 12v even if I revved it

lax-rotor

iTrader: (1)

This might not help you at all but I just read in the owners manual that a fluctation is normal for starting the engine. When running it should stay between 11 and 15 volts. any more or less and you have "a serious electrical problem and need to take your rx7 into a certified Mazda dealership for repairs."

Are you just not getting enough Current/Volts to keep the car running?

Edit: What's the condition of your battery? Mine was thrashed and needed some cleaning, but mine read voltages on the low side of the scale (pretty similiar to yours), but once I cleaned it up and put some contact jelly (about 3 bucks or less at an autoparts place) on the terminals I got an increase of around 2-3 volts. Could also check that too (unless that is you just replaced the battery).

rurouni2071

I just dropped a new battery in a couple months ago , after a few minutes of running at 14.5 it kicks off.. just all of a sudden

I took it out again and I think I'm going to open it up see if I can rebuild it based on the FSM instructions

Icemark

sounds like the regulator may be shot in the alt.

Kenteth

I broke an alternate belt when I was 20 miles from home. I drove all the way on battery power alone. So its not fair to say it can't run without an alternator providing power. Not sure weather the alternator regulator harness has somethign to do with it though?

Icemark

I think he means the battery disconnected, not that alt disconnected

rurouni2071

all right I got the s4 alt in and its doing okay , by okay I mean it runs the car well .. but not with stereo and lights on together,

I still havent gotten a chance to pull that S5 alternator apart but I'm going to try in the morning

Icemark

well that tells you that it is not an electrical system issue, but either a bad alt or the S5 alt was not wired correctly.

Common if you have a high power stereo or a alt that is starting to die.