Options for powering RaceCapture - OBDII vs Terminal Block.

Race Capture Pro hardware installation- power, wiring, physical installation, etc. See the dedicated forum for Sensor related topics

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Options for powering RaceCapture - OBDII vs Terminal Block.

Post by davef_dci »


I think this has been covered on here before but I can't find it. I'm running a RaceCapture MK3 in a Chump Car. We are attempting to use the Legacy OBDII cable so we can see some data from our ECU. The OBDII cable does a fine job powering up the MK3, but our race regulations require that we shut off our main power switch during pit stops where we fuel the car. This drops power to the MK3 and we end up needing to reboot. The MK3 generally comes up but there were a few instances when the MK3 didn't power up cleanly and we needed to futz with without before we could leave the pits.

If I switch over the to the terminal block I can run that directly to the battery (through a fuse) and ensure that the unit remains powered up at all times through pit stops - but then it seems that I would lose access to the OBDII.

Is there a way to power up the unit (via the terminal block) and still use the OBDII? What strategies have people used to prevent having the power down race capture and reboot?

As I mentioned, I think there are threads on here discussing this so feel free to direct me to previous discussions.


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Post by brentp »


RaceCapture/Pro MK3 has isolation diodes so you can safely power it via OBDII and also the molex connector and not have the risk of back-feeding power through the OBDII port. RaceCapture/Pro MK2 did not, so we warned people to not do this.

You mentioned "Terminal Block" for your MK3 and just wanted to confirm what version you have. MK3 is the black box with a 24 pin molex connector; MK2 has a green terminal block.

You can also power RCP using the USB connector and one of those phone booster batteries as a type of 'backup' that will keep the unit running during pit stops. We talked about it here in our blog post:
https://www.autosportlabs.com/use-cheap ... pit-stops/

Hope this helps! Let us know what you end up doing.
Brent Picasso
CEO and Founder, Autosport Labs
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