Hello

My knowledge of electronics is limited.

As far as I understand the OVMS module is supplied with +12V via the OBD connector. What I don't understand is where the +5V comes from?

https://github.com/openvehicles/Open-Vehicle-Monitoring-System/blob/master/vehicle/Car%20Module/v2-base/20120814-boarddesign.pdf

I'm currently trying to control a relay using the RC3 output on the PIC18F2580 as a control signal to a rely on a relay module

http://www.dx.com/p/arduino-2-channel-relay-shield-module-red-144140#.U59Qavl_t8E.

The relay module needs to be supplied with +5V to drive the relays, and my plan was to get the +5V from the OVMS module using pin 13 on the HEADER 9X2.

But I'm afraid I might blow something on the OVMS module if the relay module draws to many mA.

Any advice would be appreciated.

--Olav