Hi fellow 4Runnerers
Im trying to figure out what is the M terminal on the alternators on the newer 4Runners and Toyotas in general for, since I drive an older one that has no M terminal. I posted this in the 3rd gen section, in case someone can let me know there too.
What I want to do is upgrade my 4Runner's alternator to a higher AMP rating. The 4Runner I have is a 3rd gen purely mechanical diesel 4Runner and it originally comes with a 60amp alternator, that is sufficient for all the loads installed from the factory but... after having it for 10 years, I upgraded it with almost all stock options and extras from both the 4Runner and Hilux Surf and now Im starting to run on occasion into starter battery drain issues while driving.
The current regular winter wattage in the car is as much as the alt can provide in amps and not enough to charge the battery. And I haven't even turned ON the fog lights or use the wipers, heater seats, talk about turning ON my secondary crap like fridge and hf radio and charge my AUX battery all at the same time... It's only time until I drive 500kms and turn off the car and wont be able to start it because all the electrics and electronics have drained my starter during driving...
The alternators from the US gasoline engines are not bolt on and they are only 80amp max which is not enough. I know there are options to upgrade the alternator with a generic crap alts, but I prefer it to be calculated by Toyota and OEM quality.
I found a few options here that seem to have the correct mounting options for the 1KZ-T motor and seem to be able to fit by just changing the pulley on the alt itself. The amperage is 120 and 12v, which will be more than enough I think
, and they are from cheaper Toyotas that I don't know why the hell they would need a 120 amp alts!
The quys in NZ and Ausies use the 1HD 120 amp alt on the 1KZ, but it needs a modded bracket for mounting it (not a big deal). But since it's a bigger alt, it will protrude more towards the frame horn and I already have an engine Webasto preheater (to heat up the cabin and keep the engine warm in winter trips) mounted on the frame horn and is about 2 inches away from the current alt, which is far enough not to rub against the engine at idle.
Another reason not to use the 1HD alts, is that junk yards here want too much money for a used and abused one, because they know it's for the legendary Cruiser!
The diagram is for 5th Gen 4RUnners charge circuit. The M terminals is connected to the ECU and if applicable to other electronics, in this case AC amplifier.
All I want to know is if anyone can confirm the M terminal's function. Is it to send a signal to the main ECU to inform it of it's working condition or is it for the ECU to send a signal to the alt for control?
Im thinking that if the M terminal is only to provide a signal to the ECU, than I have nothing to worry about electrically and can just replace my original connector with the new one, and rewire the engine harness.
But if the signal is mandatory, because the ECU controls the alt in some way, then I will have to research further since I have no engine ECU and have to find out what signal is sent to the alt.
Thanks
Pavel
Linear Mode
