Aaron's SL-C build...

[Aaron H.]

I found an issue this morning.. My ISUS blue wire with yellow tracer has no invert module. I've asked Jay at ISIS to float me one. Afterall, I have to tear into the harness to fix it

I rung out my push button start button and all it good with it. Heater hoses are connected. More radiator pipe welding and weldkng in bungs in new locations for the expansion tank this afternoon.

 

[Garry 20 B]

Somebody must be off for the Holidays, you will probably have it running by the weekend.

Looks good Aaron.

 

[PeteB]

My ISIS harnes did not have inVert modules in either the fan wire or the a/c clutch wire.

 

[Aaron H.]

I think that I'll put the invert near the rear powercell for the fan control signal. This solution will make the wiring easier. . I won't need to tear into the front CAN harness.

For now I'll simply ground that wire and run the fans

 

[Dean Lampe]

Your build looks great! I am looking forward to your first start video!

 

[Aaron H.]

Thanks Dean... I'm putting in the time for sure. I was wrenching at 2:30 am.

 

[Dave Forster]

I'm confused.

Doesn't an invert module take a 12 v output from the ISIS system and use it to trigger a ground?

Why would this module be required for either the air conditioning compressor or the fans?

Isn't the Vintage compressor already grounded through its case and therefore requires a 12 v output? and can't the ISIS 12v output be used to trigger the fans as is?

 

[Alex]

I'm confused.

Doesn't an invert module take a 12 v output from the ISIS system and use it to trigger a ground?

Why would this module be required for either the air conditioning compressor or the fans?

Isn't the Vintage compressor already grounded through its case and therefore requires a 12 v output? and can't the ISIS 12v output be used to trigger the fans as is?

the fan power-on from the ecu/fuse box (assuming you're using the gmpp ecu setup) is 12v, so you need to convert it to switched ground for the isis to use

the invert converts 12v power from an item (e.g., fuse box) to switched ground for the isis to use in order to be able to have control over an item.

 

[Aaron H.]

Correct Alex... The fan power from the GM fuse panel into the rear ISIS CAN harness needs to be changed to a grounded input to ISUS. It in turn turns on an output at the front power cell to turn on the fans. I've made a complete wiring diagram for my SL-C. I'll know where everything is branched which will make any future troubleshooting easier.

 

[Aaron H.]

I never thought I'd spend soo much time on radiator piping. It's almost done.

 

[Aaron H.]

At least it fits like a glove.

 

[Eric McClellan]

the fan power-on from the ecu/fuse box (assuming you're using the gmpp ecu setup) is 12v, so you need to convert it to switched ground for the isis to use

the invert converts 12v power from an item (e.g., fuse box) to switched ground for the isis to use in order to be able to have control over an item.

Wouldn't it be easier to bypass ISIS unit and run a relay straight from the GM box?

 

[Aaron H.]

How is that easier? The ISIS system is designed to be plug-and-play. It already has the relay capability built-in to drive the fans. The whole point of that system is to get away from a whole bunch of relay wiring.

Yes, you could do exactly what you're suggesting.

 

[Aaron H.]

Pipes are done.. Coolant goes in tomorrow. I also modified my exoansion tank ( added bungs ). A bit of wiring and then the big GO!!

 

[Dave Forster]

Thanks for the tips, guys!

I just re-read the instructions on pg. 24 of the ISIS installation guide ("Connecting the Cooling Fan Trigger Wire to the GM Fuse Box") and it says to simply connect the GM fuse box cooling fan output wire directly to the identified ISIS wire. I couldn't find anything in the manual about needing an additional module. Is this something normally included within the ISIS modules so that the instructions as written would work, or is it just something that the builder needs to figure out on their own (or by stumbling across it on the forum)?

 

[Aaron H.]

Dave..

This ISIS wiring harness issue has been discussed on the forum several times. Some of the harnesses had the ISIS invert left out of them. If you simply connect the GM fan wire to it you will burn up the MaterCell. You need to check to ensure that the + 12 VDC output gets converted to a ground going into the MasterCell.

These along with other items became clear as I was creating a full wiring diagram for my SL-C.

 

[Eric McClellan]

Dave..

This ISIS wiring harness issue has been discussed on the forum several times. Some of the harnesses had the ISIS invert left out of them. If you simply connect the GM fan wire to it you will burn up the MaterCell. You need to check to ensure that the + 12 VDC output gets converted to a ground going into the MasterCell.

These along with other items became clear as I was creating a full wiring diagram for my SL-C.

Aaron,

I saw the discussion before but I'm not clear on how to check my harness for this issue. Could you explain or perhaps someone has photos to illustrate this better?

(I'm not a very good reading learner, much better 'talking/seeing' learner)

Thanks,

~Eric

 

[Aaron H.]

Call me and I'll explain it. 765-490-5383

 

[Aaron H.]

Exhaust tips are welded and polished.

 

[Joe Moto]

Happy New Year Aaron, Your project is looking better all the time. Looks like it won't be long before the body goes back on and down the road you go. The plastic tank above you battery is...? Window washer fluid, radiator over flow? Thanks for the info and keep up the good work.