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MICK
January 24th, 2010, 10:22 PM
I was checking out my misses VY V6 and was getting hang up with searching for the heartbeat. I found on some instances that it would connect the second/ third time I tried. Can anyone tell me what the deal is with the heartbeat on the bus? Which module is the heartbeat referenced to please?

Hummm must hack into VY PCM, having trouble sleeping, drank all the coffee....:)

Cheers

Mick

Blacky
January 25th, 2010, 08:36 AM
The heartbeat is a message usually sent by the BCM (or ECM) depending on which module has been configured as the "master". It is a signal to the scan tool that the scan tool may transmit a message immediately after the heartbeat.

When you "display chatter", look for a short non-changing message that has the most time after it and before the next chatter message. That is usually the heartbeat frame.

Regards
Paul

MICK
January 26th, 2010, 10:19 PM
Thanks Paul,

Your input was very helpful!

RE: "Tampering"
Special note to ones self: Must re-enable chatter to BCM prior to disconnecting from vehicle. Special surprise waits otherwise.


Thanks

Mick