Am I correct that the purpose of the ASD relay is essentially to offload electrical load from the ignition switch? eg, the ignition switch is turned on, relay is energized, and various switched systems now how power; ignition switch is turned off, those switched systems are now de-powered?

To a slight extent. The Auto Shutdown Relay gets energized when the Ignition Switch is turned ON and the ECM/PCM has successfully read the chipped code off the ignition key.

The Ignition Switch still carries the electrical load to all the electrical units ie. PCM/ECM , BCM, Fuel Pump if fitted, FCM, SKREEM etc. The ASD relay supplies power to the Injectors/Spark Plugs.

All Blowers, Headlights etc. have nothing to do with the ASD Relay.

If the PCM/FCM senses that there is a problem with the SKREEM system it will drop out the ASD Relay and the engine will not fire.

All the modules will get their power from Fused + Battery voltage.

If you look through the Wiring Diagrams Section 8W in the Jeep KJ Service Manuals you will see that the Modules/Blowers/Lights get their power through several fuses...ASD Relay only supplies power through a 30 Amp fuse.

http://www.colorado4wheel.com/manuals/Jeep/KJ/

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2002 Export CRD

Interesting. The thing that caught my eye about it is that it's also responsible for one side of the radiator fan relay coils... I wondered if it was part of more circuits. If it's not, then I've got no hesitation in stealing another amp or so from it.

I'll have a look at that fan relay circuitry you have mentioned...the ASD Relay drops out when ignition switches off so maybe they want any electrical cooling fan to drop off as well.

Most Digital Multimeters only read up to 10 amps DC so you can't put that in series with the ASD fuse....worst case situation is you blow the 30 Amp fuse.

The Starter Relay is identical and makes use of a 40 Amp Fuse #8!

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2002 Export CRD

I have a question about this...
I am working on doing a crd swap and if I am understanding you correctly it sounds like the computer, after verifying the key, gives the ASD relay power? I have been looking at wiring diagrams today trying to figure out how to get rid of the BCM and the Key Immobilzer...

So if I got rid of the bcm and the key immobilizer I could turn o. The and with ignition power???

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2005 KJ Crd 2.8L swapped into 1976 FJ40 with 2010 auto trans
Head studs, deleted
Yeti tuned
Suncoast torque converter
Sasquatch turbo
Cummins lift pump
HDS 001 stat housing w/190 thermostat
Trans temp, egt, ultra gauge gauges
email 84landcruiser(at)gmail(dot)com

I have some questions about this as well. I am looking into doing a CRD swap.

If the Key Immobilizer kills the ASD? Can a person remove the Key Immo and the BCM, then just power up the ASD with key on? Then the Immo would be gone... Which would be ideal for my swap.

Any help would be greatly appreciated.
Thanks.

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2005 KJ Crd 2.8L swapped into 1976 FJ40 with 2010 auto trans
Head studs, deleted
Yeti tuned
Suncoast torque converter
Sasquatch turbo
Cummins lift pump
HDS 001 stat housing w/190 thermostat
Trans temp, egt, ultra gauge gauges
email 84landcruiser(at)gmail(dot)com

I don't think the ECM will function without the SKIM unlocking it. Defeating the immobilizer requires modifying the ECM directly.... BDM, etc.

I wondered that... But, I could just keep the Skim and get rid of the BCM, I think the Skim is only 4 wires. And hide it and the key under the dash...

I was just hoping to eliminate all of it for simplicity.

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2005 KJ Crd 2.8L swapped into 1976 FJ40 with 2010 auto trans
Head studs, deleted
Yeti tuned
Suncoast torque converter
Sasquatch turbo
Cummins lift pump
HDS 001 stat housing w/190 thermostat
Trans temp, egt, ultra gauge gauges
email 84landcruiser(at)gmail(dot)com

There is a ton of info out there on removing the immobilizer from Bosch EDC16. It's very well understood I think.

The issue I *think* with doing a swap will be providing some inputs the ECM expects to come from the CAN network. I'm thinking things like vehicle speed. I'm not sure the ECM is actually aware of the BCM in the strictest sense... I think that is what the FCM does... Bridges the ECM to all the other vehicle systems. Probably the FSM can give some clues. In fact, probably any of the many EDC16 hacking forums will be useful here, since it will expect about the same IO regardless of whether it's in a Jeep. VW, or even a Kia. It was VERY popular!

I unplugged the BCM and the ABS unit and the motor and trans worked just fine. When I did a scan on the whole system, it just said No Communication with the BCM and ABS. I kept the Skim, it is taped off to the side with the chip key in it. Just thought I would let you know what I found out.

_________________
2005 KJ Crd 2.8L swapped into 1976 FJ40 with 2010 auto trans
Head studs, deleted
Yeti tuned
Suncoast torque converter
Sasquatch turbo
Cummins lift pump
HDS 001 stat housing w/190 thermostat
Trans temp, egt, ultra gauge gauges
email 84landcruiser(at)gmail(dot)com

For future reference there may be some difference on inputs from 2005 and 2006 models too.

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05 Blu LIM, OME GDE Tbo, wk II 245/75/17, KC Lights, bull bar, 195K H TC
05 Blu Lim, Dayton, GDE HT, 255/75/18 , 210K , H TC
06 Bla Lim, GDE Eco, Destination AT 245/75/17, 151K, H TC
06 D Khaki Lim 126K wkII Eur TC
05 D khaki Lim 145k refurbishing
All CRDS: Fumoto, Lift , Fan Shroud mod, fuel head Gen II, SAMCOS,self TB, 2 Mic filt, Hayden