J1850 communication with 2 controllers (ECU & Dakota digital)

[takid455-2]

Have an LS1 ECU with Dakota Digital gauges set. Have 2 ODB2 ports (1 for the gauges & the other for scanner, ect). Been informed via DD that scanners can't or don't like to see more than 1 controller at a time. This makes datalogging with active gauges impossible. One option is a switch on the data line to the gauges for when data logging is needed. Is/ are there a way to datalog & have gauges?

Have the MPVI3

[aaronc7]

This isn't just old J1850 VPW stuff, modern CAN based diagnostic systems are the same way and designed for 1 on 1 communication.

I ran 2x Aeroforce interceptor gauges on my C5 and you had to set the polling rate to really slow for both of them or else it would freak the car out instantly. Even on low polling speed, every now and then two requests would be too close together I suppose and the instrument cluster would go berserk.

MPVI is always going to try to log at max possible speed, so it won't be possible to use another device at the same time.

[takid455-2]

Thanks for the confirmation. Snipped the data line to the gauges & ECU communication was back. Adding an inline switch to the gauges & hope it works.