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JJ Alfano
06-09-2011, 07:11 PM
My SR alternator wont charge the battery, and when I disconnect one of the terminals to the battery, it shuts off. (I could take battery out with KA and car would still run, so Im assuming SR should do the same.)

Here are the quick facts.

- SR20 lower harness came with motor, motor ran fine and alternator worked fine in an american s13 prior to me getting it.
- KA24 lower harness came from my old motor and worked fine.
- Neither the KA nor the SR harness is allowing the alternator to work properly.
- The alternator tested good at Autozone.
- Alternator fuse is good.
- All plugs are plugged in properly, and all grounds are grounded.

jesse_s13
06-09-2011, 07:13 PM
Did you test how much power it was sending to the battery?

TC240
06-09-2011, 07:16 PM
I don't know how Autozone's tester works.... but the one at Advance has the ability to test amperage as well as voltage.

Just a side note.

JJ Alfano
06-09-2011, 07:27 PM
Did you test how much power it was sending to the battery?

Do you mean stick a multimeter on the positive terminal?

PoorMans180SX
06-09-2011, 07:29 PM
Autozone tester is hit and miss. Sometimes it won't detect a bad diode trio (rectifier bridge). This is probaby your problem. Get a new alternator, retest.

jesse_s13
06-09-2011, 07:38 PM
Autozone tester is hit and miss. Sometimes it won't detect a bad diode trio (rectifier bridge). This is probaby your problem. Get a new alternator, retest.
this is also very true.
Do you mean stick a multimeter on the positive terminal?

Yeah on the pos and neg on battery, turn on and make sure its between 13.8 and 14.6 (i think). Then put a load on it headlights on and heater fan on high. It will drop a bit but then return back to the normal range.

EmericanA
06-10-2011, 10:55 PM
dead short .. just found mine in the s13 yesterday.

the a/c system e-fan was short killing my inst. panel, aftyer remove the fan plug .fuses stay in tact and dash operates correctly tach, etc


did you check if all other fuses are functioning? could be worse

camaro379ss
06-11-2011, 07:38 AM
I agree with poormans180sx.