limp 7730

[Fisystems at aol.com]

Right, but to funny thing or not so funny is if I leave the power on and just 
hit the crank button it will start in the limp mode every time. I have 
checked the power wires while it's running and cranking and everything looks 
OK. Remember after it starts its fine. No codes and makes good power.

Ign 12v           A6
Grd               A12
Batt 12v         B1 moved to A6
Fuel pump     E13
Batt              C16
Grd                D1
Grd                D6
Grd                D7

There are a few wires in the ECM plug that I cannot identify
A3 RED ??
A9 ??
C4 ??


In a message dated 5/10/2001 12:35:46 AM Pacific Daylight Time, 
ludis at cruzers.com writes:

<< The '730 has two power input circuits.  It draws most of it's power from
 the (normally unswitched) "memory" power input.  The "ignition"
 (ignition switched) power input mostly tells the ECM to wake up or go to
 sleep.  (A few outputs are powered by the ignition supply.)
 
 I don't know what happens when you switch the wrong power input.  It
 might be that the power supply chip gets confused.
 
 
 GM's software (at least of the generation that would be used in a '730)
 can only handle one engine run per boot.  When the engine stalls, the
 ECM resets itself.  That means it'll reboot for the next engine run. 
 This also means that a scan tool will lose the connection.
  >>
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