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https://yabb.autonerdz.com/cgi/yabb2//YaBB.pl >> >> CAN and multiplex https://yabb.autonerdz.com/cgi/yabb2//YaBB.pl?num=1425274333 Message started by fisher on Mar 1^st, 2015 at 9:32pm

Title: CAN and multiplex
Post by fisher on Mar 1^st, 2015 at 9:32pm

Might someone steer me towards some CAN and multiplexing literature fit for an automotive technician?

Title: Re: CAN and multiplex
Post by Logic on Mar 1^st, 2015 at 11:16pm

Fisher,

I have been consistently doing that, there is quite a lot of information here that I have posted....

Title: Re: CAN and multiplex
Post by Derreck on Mar 2^nd, 2015 at 11:51am

http://www.autonerdz.com/yabbfiles/Attachments/can20.pdf

Here's a good start Fisher.

Get some coffee ... it's a tough read ;)

Title: Re: CAN and multiplex
Post by fisher on Mar 3^rd, 2015 at 8:24pm

Thank you fellows. I found your stuff, Logic. It has been my first experience with a CAN system these last few weeks; a Ford E-450 van with 6.0 litre. It is an ex-ambulance/emergency vehicle sold to my employer by an unscrupulous player, I think.
It has multiples of codes, some related to the CAN network and others from differing modules regarding low voltage or open circuits. I will probably work no more on it as practically any components on it are inaccessible except with more hours of disassembly and removal of parts for to get access to the components than I want to spend on it. Let us see what the local dealership can do for us.
I did get a capture of it's network but am having a hard time getting it to post here...

https://yabb.autonerdz.com/cgi/yabb2//YaBB.pl?action=downloadfile;file=Ford_E-Series_Van_2008_Diesel_20150301-0001.psdata (10092 KB | )

Title: Re: CAN and multiplex
Post by Tom Roberts on Mar 4^th, 2015 at 8:30am

Fisher,

Not sure where all that waviness is coming from on your CAN lines.

If you deploy a math channel A-B it cleans it right up.

Title: Re: CAN and multiplex
Post by fisher on Mar 4^th, 2015 at 6:00pm

I see what the math channels proves; that the two are parallel to each other...how about this trace?

https://yabb.autonerdz.com/cgi/yabb2//YaBB.pl?action=downloadfile;file=2008_E450_CAN_and_issues.psdata (327 KB | )

Title: Re: CAN and multiplex
Post by fisher on Mar 4^th, 2015 at 6:02pm

It is at moment 706.4.

Title: Re: CAN and multiplex
Post by Logic on Mar 11^th, 2015 at 3:07am

I have come across a case of CAN multiplex today where there are several signals in one byte of a CAN message where each bit is a different signal, not just each byte/s of the CAN message