Alternator settings?

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Posts: 4
Joined: Thu Jul 26, 2018 8:34 pm

Alternator settings?

Postby jrporkchop » Tue Feb 12, 2019 12:17 am

I've got a '02 NB 1.6 which is running a stock setup. Using the ME221 I get an issue with the voltage where it doesn't reach it's target voltage of 14.9v for charge or 13.7v for run. The voltage seems to fluctuate between 11.8v to 12.6v on charge.

Running high duty >95% will get it to 12.0v to 13.0v, running a lower duty cycle seems to lower the voltage. I'm aware that the 99-05 MX's have a different alternator that have an internal regulator and require some form of control from the ECU.

Using the stock ECU the Voltage is correct, starting will run up to 14.9v on charge and stay solid. Does anyone have an idea as to what's wrong with the config?

Current Alternator Settings;
Mode: PID
Inverted Output: Yes
Start Delay: 2s
Charge Volts: 14.9v
Charge Time: 15
Run Volts: 13.7v
PWM Freq: 250Hz
PWM Min: 1
PWM Max: 95
CL Params
PID P: 0.3
PID I: 200
PID Interval: 100ms

Posts: 1
Joined: Thu Feb 14, 2019 4:55 pm

Re: Alternator settings?

Postby creatored » Thu Feb 14, 2019 5:00 pm


I had the same problem. My Alternator was working it's arse off but wasn't charging, it doesn't sound to healthy now :lol: .

I've got a Mk2 1.8 and changing it to 'Fast Switch' worked for me. It's now charging correctly, and not putting to much stress on it

Base map had it set to PID which didn't work.

Posts: 4
Joined: Thu Jul 26, 2018 8:34 pm

Re: Alternator settings?

Postby jrporkchop » Mon Feb 25, 2019 9:07 am


So a catchup with this issue, I followed creatored's advise and it sort of worked. The voltage started to fluctuate between 12v and 14v, and seemed to create a ripple voltage at idle.

So I suspected the alternator, so after getting hold of a used original and installing it the voltage returned a fairly stable voltage.

It seems that sometime in the car's past the alternator was replaced with a pattern part.

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