Is the charging voltage regulated by the ECU?

Can the alternator run correctly if the warning light is absent from the dash?

Is there a way of running the alternator without either of the above?

Just trying to clear up some urban myths/speculation and get some facts

 

Martin or Gandalf on FFOC should know this mate.

 

Yeah, will drop them a PM...

I'm just trying to establish if i can wire round the issue of removing the factory ECU and clocks without having to pay a couple of hundred quid for a race alternator.

I know there is a solution but i'm loathed to just throw money at the problem!

 

Found this, looks like no, unless they have an olde stylee back up built in;

*******************************
The BF Falcon uses a new generation 130 amp Mitsubishi alternator, 5R29-10300-AC, known as a smart alternator. It uses a voltage regulator with three terminals: A (or S) terminal, SIG (or RC) terminal and FR (or LI) terminal. The A terminal senses the voltage at the battery, the SIG terminal receives a pulse width modulated (PMW) signal off requency 128 Hz from the ECU to control regulating voltage and the FR terminal sends a signal to the ECU indicating how hard the alternator is working.

The Ford Focus also uses a smart alternator, manufactured by Magneti Marelli or Motorcraft. They use the same regulator plug as the 130 amp Mitsubishi alternator. All of these alternators can be bench tested using a suitable PWM.

************************************

 

The Voltage is regulated by the ecu.

The wiring is well known for going faulty aswell,causing a drop in charging voltage.

 

we change alternaters on focus's all the time.they are rubbish.the alternator is controlled by pcm and told to charge when requested.the smart charge generator in the back is dormant until pcm asks it to charge.normally it packs up and cant work as the request and stop is so frequent.
i would imagine cars could run without a charge light as the alternator has its main lead from battery then the 3 pin plug,1 wire is a fused battery feed,one is signal to and from pcm and the other pin is the light request wire.
hope this helps a litle bit mate as from the amount we have changed and reading up on etis,thats my understanding of 'smart charge' alternators

 

Hmmm - might start looking at some earlier zetec ones without the 'smart charge'...

I guess nobody has tried disabling the 'smart charge' circuit?

 

i ran a 1600 zetec se in my ka, had no wiring for the alternator, and that ran fine no issues at all, i should have a pic off one you may be able to get that to work?

 

will, would a run of the mill RS turbo etc alternator not fit with the wide pulley on? That's what's going on mine, albeit mounted at the front.

Rick

 

Going to go and have a rummage in The Diva's alternator collection one night this week

 

Just a thought, if the smart charge system is PCM dependant, if you run a totally after market ECU then it may not effect running...

 

It's whether or not it'll give a suitable charge output if the 'Smart Charge' aspect is disabled.

The reason i'm keen to do the research on this now is because with the supercharger on, alternator removal isn't easy!

That and the fact i've been caught out before with a race car alternator - we paid £500 for a lightweight alternator on an Evo that didn't charge below 1800rpm... Which meant it kept dying at idle

 

surely losing the stock ecu will open a world of issues? does it have nothing to do with the abs, immobiliser etc?

are you planning on removing the stock ecu and wiring and using a dig dash and aftermarket management?

Interested in this too on my new project, but thought there might be abs, ps and other electric issues from it.

 

I know Jon@ShawSpeed did this to one on a Fiesta ST which is ECU controlled...

 

they do still charge with the smart charge plug unplugged,they come in all the time with the light on but still charging merrily away at 14 volts.

 

as he said.

 

i thought this as i want to loose mine completely also

 

Replacing the stock ECU with an AEM race unit and the dash with an AIM MXL Strada

ABS - don't want as the car is going to be on AP 362 6pots and used for track primarily.

Will have an aftermarket alarm/immobiliser on it as well.