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CAN BUS timeout

PostPosted: Sun Oct 02, 2022 11:30 am
by TurboTito
I have a PNP M150 system that I purchased from John Reed for my 2009 CTSV. Everything has been working great until I installed an aftermarket radio in my car. The radio required the use of 2 external interface devices so that I could still use my back up camera, and my steering wheel controls for radio volume. I believe that somehow something in that system used the CAN BUS for communication to the BCM.

Now my problem is ever since then I have a CAN BUS timeout for both Exhaust Lambda Bank 1 & 2 LTC diagnostic. So, I have no 02 readings and I cant continue in the tuning process with the car. Everything else with the car performs as it should, just no 02 readings now.

I reached out to John on friday, and will wait for him to respond...but I decided to go ahead and ask here to see if anyone had any input.

I had the battery disconnected when i did the install, but could the Lambda CAN to Dual adapter have shorted out/went bad?

Re: CAN BUS timeout

PostPosted: Mon Oct 03, 2022 4:33 am
by David Ferguson
There may be a CAN bus address in-compatibility with your new CAN devices and the MoTeC LTC. John should be able to help you sort that out.

What happens if you disconnect the new CAN devices, does your Lambda come back?

Re: CAN BUS timeout

PostPosted: Mon Oct 03, 2022 8:57 am
by Stephen Dean
Are the LTC's running at 1M CAN Bus Speeds? The new devices may be set to run at 500k as this is the OEM default CAN Bus Speed for High Speed CAN, in an entertainment system they may even be running at 250K. If there is a difference in the Bus speed that different devices are running at, then the CAN Bus will fall over.

Re: CAN BUS timeout

PostPosted: Mon Oct 03, 2022 12:08 pm
by TurboTito
SDean wrote:Are the LTC's running at 1M CAN Bus Speeds? The new devices may be set to run at 500k as this is the OEM default CAN Bus Speed for High Speed CAN, in an entertainment system they may even be running at 250K. If there is a difference in the Bus speed that different devices are running at, then the CAN Bus will fall over.


Yes they are both set to 1M speed and I verified it with the LTC program as well. Tomorrow I will try to plugging the stock radio back in and see if it helps. It is a hassle in this car, but I gotta find a lead somehow.

Re: CAN BUS timeout

PostPosted: Tue Oct 04, 2022 8:25 am
by TurboTito
I plugged the stock radio back in and it didn't fix the issue.

Some stuff in the CAN BUS and LTC settings just aren't looking right to me. I'm going to reach out to John and get his feedback on it. It is just weird that one day everything works and then the next it doesnt.