M2-atx hard off when turning ingnition off

**WuNgUn** · 02-27-2009, 08:08 AM

Best of luck!

**jmhalder** · 06-04-2009, 04:29 PM

same symptom, 95 240sx, m2-atx... tested w/multimeter, no symptoms on the bench either, must spike voltage or go negative... this should be in the m2 faq.

**trader007** · 08-12-2009, 05:05 PM

Originally Posted by jmhalder

same symptom, 95 240sx, m2-atx... tested w/multimeter, no symptoms on the bench either, must spike voltage or go negative... this should be in the m2 faq.

i got this dreaded problem today.

m2 works fine when i start the car, but when i go to shut it off the motherboard powers off immediately and then restarts- just like it lost power for a split second. then, after a few more seconds while its trying to reboot, the m2 sends the shutdown signal as its supposed to and it shuts down.

thing is its been working fine for weeks, and nothing that i know of has changed. these problems are getting to be such a pita... im starting to question the durability of the m2atx (already returned one of them!)

**trader007** · 08-12-2009, 05:50 PM

and once again, as soon as i post to a forum i figure out the problem

m2 was powered off acc for climate control, and while normally the truck doesnt shut off the acc while starting it DOES shut off the power if the A/C is left ON. smart setup i guess, because it fooled me. there is no doubt this could have been the reason i have had weird shutdown problems in the past... as long as the A/C is OFF when i turn off the ignition, everything is peachy.

so right now im switching things up and m2 will get power from a dedicated battery circuit. for control, the remote outputs of my 791xv remote starter will fire up a relay to switch the REM on the m2atx. this way i can remotely fire up my pc if i want to, and all other problems should be eliminated.

**tbird2340** · 10-21-2009, 07:21 PM

I'm having this same exact issue. M2 works fine in bench but when I put it in car it cuts power hard when the ignition turns off..

I have the M2's constant connected directly to the battery, the switched connected directly to an ignition wire at the ignition harness, and the ground to ground..

It powers up correctly (5 seconds after IGN wire is powered).. It gets into Windows fine and runs fine.. However, the second I turn the vehicle off power is instantly cut and the computer shuts off..

I metered my constant during the whole process and it never dips under 12V (unless my meter isn't fast enough to catch it)..

So WTF could be wrong?

I have the jumper on B but it does the same thing on A as well..

Thanks

**WuNgUn** · 10-23-2009, 07:12 AM

Without shutting of the IGN, remove the wire from the IGN leading to the M2 and see what happends...
Also, what do you mean the 'ground is to ground'? It's attached to the chassis of the car?

**tbird2340** · 10-23-2009, 07:24 AM

Yes, ground is attached to chassis..

**WuNgUn** · 10-23-2009, 08:10 AM

Some vehicles have more than 1 IGN and more than 1 ACC lead at the key...
Where are you getting your wiring info for your vehicle?

Get more specific info here...
http://www.the12volt.com/installbay/vehicles.html

It could also be a defective M2...all the M series PSU's are garbage...have you been in contact with their tech support?? They are usually pretty helpful in that regard at least!

**tbird2340** · 10-23-2009, 08:14 AM

Originally Posted by WuNgUn

Some vehicles have more than 1 IGN and more than 1 ACC lead at the key...
Where are you getting your wiring info for your vehicle?

Get more specific info here...
http://www.the12volt.com/installbay/vehicles.html

It could also be a defective M2...all the M series PSU's are garbage...have you been in contact with their tech support?? They are usually pretty helpful in that regard at least!

My vehicle only has one ign line and the accessory line is a "mux" line so I don't think I can use that.

I'm tapping in right at the ign harness.

It's not the M2 as I've tried two and it happens to both.

No, haven't been in contact with them.. I'll try to find their contact info and see what they say.

**tbird2340** · 10-23-2009, 07:17 PM

Originally Posted by WuNgUn

Without shutting of the IGN, remove the wire from the IGN leading to the M2 and see what happends...
Also, what do you mean the 'ground is to ground'? It's attached to the chassis of the car?

Ok, I started the car with the IGN wire disconnected.. With the car running I then applied the IGN wire to the M2.. It powered up correctly after 5 seconds.. I let it run for a minute or so and then removed the IGN wire from the M2..

It began the hibernation process.. While it was still in the process I turned off the car.. It didn't shut down and continued hibernating correctly..

So, it has to be something going on with the IGN wire only when the car is shut off because it works fine when I manually remove the IGN wire from the M2..

How can I fix this?

Thanks