TIU Causing Z4000 to Overload

THe TVS Diode is shorted.  Does this do it for all channels or just Fixed one?  Try each channel.  G

So far just fixed 1.  It is a customer TIU and he does not have the means to power it through the AUX.  I can check the other channels later and find out if they're ok or not.

Thanks G.  Hope you're feelin' better

I am thank you.  It is the TVS most likely.  Not hard to remove and replace.  Once done you need to check that DCS signal remains with no issue.   G

FWIW, checked remaining channels, pass power and signal without difficulty with TIU powered by AUX power.  Thanks for the help!  We have some older TIU's with other problems and can rob a TVS diode from them without having to wait on MTH for parts!

Customer will be happy :d

I have them in stock if you need some.  G

You can get a TVS from Digikey in a couple of days, and they only charge a couple of bucks for shipping small orders First Class.  I'd probably get a few if I were you.  If you buy ten of them, the total bill will be less than $10 including shipping.

1.5KE36CA at Digikey

Thanks for the info Guys.  Appreciated.

This is a friend's TIU, when getting ready to return it, is there anything I should tell him he is doing wrong that may have caused this diode to crash?

Not really, it's just a transient that causes the TVS to short.  The point of the TVS is to protect the other stuff from the high voltage spike, and when overloaded they frequently fail in a shorted state.  They're very easy to replace as they're a nice big part.