1uz alternator not 'doing it's part'?

[stradlater]

My battery is good, and will hold charge nicely once I charge it up with an external charger.

But, it would seem to me that my alternator is not charging.

After a little while running, the battery ends up flat (good indicator for starters) and also the ECU is showing the battery voltage as something below 12 (starts at 12 and heads south to 11ish.)

I would have thought the voltage was supposed to be up around 12.7ish?

Is there any trick to the 1uz alternator wiring? Or is it just a case of if the big thick wire is in place, it should work?

I've got the original wiring (three pin plug) plugged into the back of the 1uz alternator, but from what i can see, even if that was WRONG it wouldn't actually STOP it from working, it would just not show me things on the dash?

is that right?

[RA35GT]

No that is not quite right.

There are probably the following wires in the three pin plug.
These three wires control the regulator and need to be connected properly.
IG - Must be ignition switched +12V
S - Sense, connected to battery + terminal through dedicated wire.
L - Lamp, connect to lamp in dash.

The big wire is the alternator output, it only works if the above three are connected.

[woggin]

Voltage regulator still good?? maybe it went south!!

wat kinda car is it in?? i know on uzz30 soarers the powersteering pump leaks onto the alternator, shorting the alternator out!

look for leaks?

[TRD-12A]

Very important you have the 12v ignition feed, the light on the dash must be working otherwise it will not charge and ofcourse the wire running from the alternator to the battery itself and as 7M-GTE MX73 The main cable (the big One) is the output which actually sends the charge to the battery.

If you have all these things at the alternator then the alternator is buggered needing a rebuild

[stradlater]

So even if the charging light isn't there it won't work????

[madmont]

As far as I know the indicator light is just that and does not affect the operation of the alternator

[stradlater]

But that 'sensing' one is pretty key I would have thought?

[madmont]

It is only an indicator light makes no difference to the charging

[RA35GT]

http://www.toymods.org.au/forums/sho...ght=alternator

[Supra967]

^ helps to know where to find stuff. Shame the pics don't work.

I was recently playing around with a 7M altenator. No charge with only field wire connected (2A draw for field winding).

Hooked up the load sense wire and charge went quickly to 6 amp before i backed off (10A fused DMM), that was with hardly any load and no charge light wire hooked up.

[stradlater]

There's a rather good guide that Witzl put up, which links to a PDF, that is awesome.

Can't remember where either is now though.

[TRD-12A]

The light needs to be working otherwise it wont charge the battery

[stradlater]

Yeah, I've just noticed that now. pin 1 and 2 work, but 3 doesn't, and the battery isn't charging..

[mick08]

Found out the hard way few years back that you do actually need the battery light on the dash to 'excite' the alternator to charge, it will not charge sucessfully without it, killed a $300 optima battery to learn that lesson by charging it killing it charging it killing it untill it wouldn't take a charge anymore.

[TRD-12A]

have you put the motor into another car or is it in the car it came from??

If you havv'nt wired it in all you have to do is give the light a negative feed and on the other side run the wire to the alternator at pin L (light) then when alternator is charging it removes the power going to the light therefore turning the light off

If it's a factory fit up and pin3 is the light wire and nothing is happening check the globe in the dash, check continuity through the wire with a multimeter(checking for a break) if these are all ok then alternator will be the problem.