Motec M130 Evo X

Hi all

As stated in the title I have a Motec M130 EVO X GSR. The car has already been tuned. It starts right up but I have everything working but the alternator is questionable. The alternator is does charge with the motec installed. If i install the factory ecu and start the car, the alternator will charge. And then if I reinstall the Motec the alternator will continue to charge. But if I disconnect the battery or the battery dies the alternator no longer charges. Has anyone else experienced this and if so what was your solution.

Thanks in advance

Mark,

This may not be related to the ECU. The alternator may have been damaged by over draw attempting to charge a dead battery. Ideally you charge dead batteries with a charger, then start the engine. I know this isn't always possible...

If you'd like to export your motec package and upload it we can see if alternator control appears to be active, see if settings look reasonable.

When the battery dies I always charge it to 85% capacity before starting. Battery is relatively new but doing electrical work with KOEO kills it pretty good. Initially I would disconnect the battery in working on car with the doors open or key in the unlock position for long periods with the engine off. But thats when I discovered the alternator was not charging. After testing all the connections for power i Replaced the alternator thinking that was the issue. When I saw that the alternator was not charging i did a deep dive and in a last ditch attempt out of desperation I put the stock ecu back in and alternator started charging. I put the motec back in and it was still charging. At some point I had to disconnect the battery to install new fuel pump wiring and when I reconnected the battery the alternator was no long charging. Mind you the dash never showed a charging fault. So I recharged the battery put the stock ecu back in verified the alternator was charging. Removed the stock ecu reinstalled the motec and the alternator remained charging. This is the first time I've ever witnessed an alternator control issue like this before.

I would agree with Mike, it seems you aren't enabling the excitation of the magnetic field.

It's common for there to be a residual magnetic field, that decays over time, in the iron core. If the alternator isn't having the rotor winding supplied a current from the MOTEC, and it's been sitting for a while, the decay may have weakened the residual beyong the ability to self-energise from the windings, but if the OEM ecu is used and excites the rotor's magnetic field, there may be enough residue to provide enough field to allow the alternator windings to produce a voltage and current, and so it charges.

When you say the dash never showed a charging fault, do you mean the bulb in the stock dash, or something else?

I ask because if the bulb has been removed along with the stock cluster to install a digital dash, I've seen that cause intermittent or no charging.