749 in a 730 - troubles

[David Cooley]

At 01:16 AM 8/12/1999 -0800, you wrote:

>I haven't quite figured out what the second interface chip (34984 or
>79435) in a 749 does.  It for certain runs the second P+H injector
>driver.  But it has been reported that the SyTy doesn't use that
>feature.  The 2nd chip might provide an extra input port or peripheral 
>control.
>
>Perhaps the SyTy code expects the functionality of this extra chip, and
>gets confused when it is missing.  That might be why 730 chips work in a
>749, but not the other way around.  (730's are missing the 2nd chip.)

Not sure what it uses to drive it, but the SY/TY has a coolant pump for the 
liquid/air intercooler that is run by the ECM.
Could be that chip is driving the relay... without it it gives a code... 
Need to disable the coolant pump code for the intercooler if that's the case.
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David Cooley N5XMT Internet: N5XMT at bellsouth.net
Packet: N5XMT at KQ4LO.#INT.NC.USA.NA T.A.P.R. Member #7068
We are Borg... Prepare to be assimilated!
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