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Biggsy
April 5th, 2007, 09:45 AM
G'day everyone and Happy Easter!

Got a question.
If you were to do a conversion in which you put an LS1 into an old vehicle, what can be done to create a MIL (Check Engine Light)?

I think the MIL on Commodores is illuminated by serial data sent to the instrument cluster.

Any way to get around this?
Any LS1 vehicle use a pin on the PCM as a direct connection to the light?

Cheers,

wait4me
April 5th, 2007, 10:03 AM
Just hook it up to the pcm output. It puts out a NEG output. so the other end of the lamp goes to + ign.

Biggsy
April 5th, 2007, 10:06 AM
Thanx.

I don't have a wiring diag as yet for the VT LS1, but I have got one for the VT V6, the V6 version doesnt have a pin for the MIL, it uses the serial data stream. That is what I was basing my assumptions on.

Cheers,

Biggsy
April 5th, 2007, 10:13 AM
The other thing I noticed on the same car model in the V6 version was that the low speed engine cooling fan gets operated by the body control module and the high speed was direct from the PCM.

Same for the LS1??

wait4me
April 5th, 2007, 10:27 AM
http://www.ls2.com/boggs/torques/2002pcm.htm

Biggsy
April 5th, 2007, 10:45 AM
:cheers:
Is it possible though, the Australian LS1's have a different pinout?
Its only a matter of code changes and some of the pins will have a different function.

I'm getting the factory diagrams next week and will have a look.

Cheers,

wait4me
April 5th, 2007, 10:53 AM
Dave, i dont think they would go thru that much trouble changing the software spare outputs to be different. Most of the inputs are all Hard component ins and outs. So they cant be changed without a board design. You should be safe. The only thing you need to do is make sure that you set up the tach output pulses and pullup to be the same for your tach.

Biggsy
April 5th, 2007, 11:01 AM
No Worries, I will still compare the pinouts next week just to be on the safe side.
Thankyou VERY much for your quick replies and your helpful information:cheers:
Have a good Easter (when it finally arrives over there!)

Cheers,

Biggsy
April 5th, 2007, 01:10 PM
No MIL enabler pin on the Australian LS1 PCM, so there must be a difference

wait4me
April 5th, 2007, 01:38 PM
If the same pin isnt being used on your pcm diagram then more than likely it is still being used. You can test by using efilive to turn on and off the mil light and see if the output is working.

GMPX
April 7th, 2007, 11:04 AM
Dave, you can use the MIL output and Low Speed fan output on the PCM, Holden only used serial data to commonise (sp?) the BCM / engine looms between the V6 and the GenIII.
ALL the ins/outs on the US PCM diagrams are available on our local PCM's, just because Holden don't show them doesn't mean they aren't there!.

Cheers,
Ross

Biggsy
April 7th, 2007, 04:44 PM
Thanx guys :cheers: