Quote:
Originally Posted by SeeThruHead
i wonder if you could put a translation layer between the MK60 that listen to its can messages, and outputs nissan can messages that emulate the original abs can messages.
An arduino that can read the mk60 can messages and then write nissan can messages (whatever the messages were the old abs was writing)
Then you wouldn't need to maintain the oem abs unit.
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The factory ABS module sends out these messages on the CAN bus:
• Individual wheel speed
• ABS active signal
• ABS warning light status
• Brake warning light (low fluid)
• VDC off light
• VDC warning light
• brake line pressure (~1500 psi at a full ABS stop!!)
• side (lateral) g acceleration
• engine torque reduction signal (for VDC)
• TCS hold gear request
Some of these signals have counters and checksum that can be difficult to calculate correctly. If the data payload doesn't have the proper format, it is not accepted by the other modules.
I think there is an easier solution:
Why not tap into the existing wheel speed sensors and have them connected to the factory ABS module AND the MK60?
• The factory ABS module only needs electrical connections.
All hydraulic connections can be removed.
This will keep the speedo and syncro rev match functions working.
• Then set up the MK60 as a stand alone ABS and connect to the car's brake lines.
This will give you better ABS BUT you won't have any traction control or stability control... which shouldn't be a problem for a track/race car.
The sharing of the wheel speed sensors may require some signal conditioning as the load is sees (current) is a little greater. If required, using a MOSFET would easily handle this task as they are a voltage switching device unlike a transistor which is a current switching device.
I will be doing my front brakes in the next few weeks and will scope my wheel speed sensors to see if the signal is a 12v / 0v pulse (hall sensor), or if the pulse is 0.5v on top of a ~11 volt signal. (magnetoresistive sensor)
Fun fact:
@ 160 MPH the wheel RPM is about 2,000 RPM (for 84.3" circumference) and that is 33.33 revs/second (2000/60). With 48 teeth on the hub tone ring, that equals a frequency of ~1600 Hz or 1600 pulses per second. This is what the ABS module processes.