MS3 loss connection and not work.

[ponthai]

fuse ok, volt input ok and I check vref already it 0 volt.

What happen? can I fix it?

[Matt Cramer]

Check if VREF has voltage off the car on a Stim.

[ponthai]

Check if VREF has voltage off the car on a Stim.

idont understand. please explain.

[billr]

Disconnect everything from the MS except the 12V power and see if Vref is still low. There should be only two wires connected to the MS when doing this test (other than voltmeter leads).

[ponthai]

OK,

supply 11.7 volt,
S12 11.7 volt
S12C 10.7 volt
VREF 0.38 volt

I found the U5 so hot. I think it U5, the top of left on the aluminum heat sink.

Can I check any volt or resistor or pin ecu?
or do something to solve this problem?

[billr]

Is the daughterboard still installed in the 40-pin CPU socket? If so, remove that from the mainboard and test for Vref again. If Vref is still low with the daughter removed, then it is probably going to take a certain amount of disconnecting or removing components on the mainboard to track this down. Are you going to be able to do that, is this a V3.0 or V3.57 mainboard (through-hole or SMD)?

[ponthai]

Is the daughterboard still installed in the 40-pin CPU socket? If so, remove that from the mainboard and test for Vref again. If Vref is still low with the daughter removed, then it is probably going to take a certain amount of disconnecting or removing components on the mainboard to track this down. Are you going to be able to do that, is this a V3.0 or V3.57 mainboard (through-hole or SMD)?

It V3.57 mainboard SMD.

I remove the daughterboard and check Vref again It is 4.98 Volt, It look good.

so next step to check this problem, Please help me...

[billr]

Do you have an MS3X? That would be the last thing to try, re-installing the MS3 (daughter) but not connecting the MS3X, then check Vref again. However, it sounds like the MS3 is bad, and those are generally non-repairable for the DIYer. How old is the MS3? It may be under warranty, contact the vendor to see about having it replaced economically.

[ponthai]

Do you have an MS3X? That would be the last thing to try, re-installing the MS3 (daughter) but not connecting the MS3X, then check Vref again. However, it sounds like the MS3 is bad, and those are generally non-repairable for the DIYer. How old is the MS3? It may be under warranty, contact the vendor to see about having it replaced economically.

I buy the MS3 with MS3X just 2 month ago from DIYAutotune.
So I reinstall the MS3 daughterboard without MS3X. And the same things low VRef to 0.38.

It maybe the bad daughterboard, isn't it?
uhm Claim only?

[Matt Cramer]

Contact us directly at websales@diyautotune.com for a daughter board warranty claim. Please include your order number if possible.

[ponthai]

Contact us directly at websales@diyautotune.com for a daughter board warranty claim. Please include your order number if possible.

OK, I send the email already.
So mainboard or dughter board error?

[Matt Cramer]

Probably the daughterboard, but the whole unit is under warranty. I've sent the return paperwork just now.

[ponthai]

I send the goods to you already.

Thank you.