MGL Avionics User Forum

Hello knowledgeable people

Some help and direction needed as ive exhausted mine. Got Blaze EMS talking to RDAC ok green flashing light, EGT & EGTs screen ok. Problem hooking up the VDO water temp sender. I just get a -45deg reading in red background. Nothing I have done has made any change whatsoever, pull up on, shorting lead directly to ground. The reading does not change, its as if the RDAC is just not seeing the sender. Ive programed it correctly VDO, 120.
RDAC Earth wired as per manual, ie engine block, then via batt -ve

Any pointers gratefully accepted

thanks in advance Dave
Forgot to add this is a new installation

We use the Echlin TS920 or TS921 water temperature sender for this engine.
This is a common part used in Ford and Mazda engines.
Have you selected the correct source for your sender in the setup ?

There is nothing wrong with the resistive VDO sender, changes ohms with a heat gun.
My plan is to see if I can get any of the spare inputs working eg the oil pressure which is a resistive sensor or LM355 OAT sensor working
Thanks for your comment

Please note the mapping of the RDAC to the Blaze EMS2

EMS-2 Analog Channel 1 = RDAC OILT
EMS-2 Analog Channel 2 = RDAC OILP
EMS-2 Analog Channel 3 = RDAC AUX1
EMS-2 Analog Channel 4 = RDAC AUX2

Regards,
Franz

Franz
Thanks so much for your input.
Ok so I configure analog channel 3 for temp and still get same error -44 deg c.
However if I connect to AUX 1 everything works fine.
So that’s a result. Still unclear as to why it not work on channel 3.
Top class and thanks so much for pointing me in the right direction
Dave