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I would expect that the Elise will work with the any standard ODB-II scanner that supports the proper protocol

Yep.

I think we already had one confirmation that a standard (ISO-9141) OBD-II scantool works fine.

The other formats use different pinouts, so it's not hard to be certain.

The fact that the CAN-Bus is also available from the same plug just adds additional capabilities, but for basic emission control and diagnostics, the Elise has to support ODB-II.

In fact, the Elise may not send basic OBD diagnostics over CANBus at all. They have no specific requirement on the CANBus and can use it for whatever data they like, so long as the OBD requirements are met on the K-Line (ISO OBD-II).

Some cars put the OBD parameters on both, but most I've seen do not.

The actual ODB-II connector under the dash is a 15 pin connector

16, if you're picky.

I'm not sure that the pin-outs for all the additional connections are standardized, but they have to be for the ODB-II standard (and most likely the CAN-Bus).

OBD-II, ISO Style, is required to be on pins 4/ground, 5/ground, 7/K, 16/pwr -- Pin 15 (L) is optional.

Some (most?) implementations skip the additional L-Line, but the K-Line (Pin 7) is required and it's the one most scantools use. If you have a metal contact at Pin 7, it's 99% certain you have an ISO-9141 OBD-II port and can use any compatible scantool.

HS CANBus is usually (always?) on 6 & 14 when present. While the bus interface is well-defined, the data on it is open to manufacturer whim and I don't yet know what Lotus is pushing out there. Like I said, it could be Beethoven, or it could be Yankee insults.

 

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If I got and OBD-II scanner, could I do the full ECU dump like the dealer will do at the 1000 mile checkup? If OBD-II won't do it, how can we? CAN bus? Something else?

The OBD-II parameters are a 'basic' set of test results, freezeframe data (for failures), and real-time parameters you can read. They're really just the lowest-common-denominator stuff that is required of a car.

It's almost entirely emissions related -- loose gas cap, faulty O2 sensor, misfires.. The data available is really generic -- a long list of standardized trouble codes.


All the manufacturer-specific stuff is either undocumented extensions to OBD-II via special PID values and so on, or a totally different data bus.

Lotus appears to use the CANBus on the ECU for their extra stuffing. The Lotus Scantool knows the right language to speak and can read all these values out and interpret them correctly.

No other off-the-shelf scanner is able to do the same -- the ECU dump needs to be done by the Lotus tool.

Any OBD-II tool can clear your Check Engine light, though.

 

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Give me one night alone with a Lotus ScanTool3 and an unsuspecting Elise and we will know all.