Chucklee

iTrader: (3)

Well, she nearly caught fire. mark8 fan (i think its a mark8 fan) melted the hi speed positive wire in the ford pigtail at the fan. Known issue there I've learned, need to put bigger wires to the fan. Popped my 50a fuse, which started a chain of unfortunate events haha.

On to what I need help on.
I want to also rewire my fan configuration completely. I was using a flex-a-lite fan controller but i want to get back to PCM controlled fans and ac.
I'm running a blue/green p59 PCM but i would like to run my fan and ac like a 99 camaro.
Can you guys please help me with a specific wiring diagram for this application?
1) My AC request and relay setup is just like a 411 pcm on a 99 camaro. I just need to run pin 33 hi speed turn on somewhere to tell fan to go hi speed when ac is on.
2) 2-speed fan

Any of your help would be greatly appreciated.

Michael Yount

iTrader: (1)

That Mark VIII pulls a boat load of current at full tilt. But I don't think it should've popped a 50A fuse....you may wanna dig in and see if something else is wrong.

Certainly you could run it off the ecu controlled relays, etc., but with that much current a soft-start/stop would really save wear/tear on the fan and the electrical system. Some of the ECU's have the ability to vary the fan speed with a pulse-width-modulated signal. And there are certainly aftermarket options for that. I run a Delta Current Control unit on both of my hotrods -- varies the speed of the fan and holds the operating temp steady. If I were running the big Mk8 -- I'd want that type of control -- not relays/switches.

Chucklee

iTrader: (3)

You are correct on many levels. After more digging I noticed the real culprit was the high speed fan positive wire at the oem pigtail. It’s common for those to melt. Mine melted and shorted out to ground probably somewhere. That’s what popped the 50a. The markVIII on initial startup will draw over 60amps but I think it hovers around 35 or so constant. I really need help with what to do then. What you say makes sense regarding soft starting it. I never done that on a swap. I need a diagram to follow to get the fan going. I don’t care if i only use the fan on high speed or use two speed but I definitely must have AC trigger setup for fan whatever I do. I prefer using the pcm controls. I’m running a 320a alternator so I’m not really worried about the soft start I suppose. I also will be using 80amp relays for the fan. They are cheap, no reason not to. Going to run 8 gauge minimum for the fan wiring too. The fan hopefully will last doing that lol. A soft start would be a plus though. Anyone else have a diagram I could follow?

67Skylark

Attached is how I ran my two speed fan. I'm using the E38 PCM to control the low speed as I never need high speed for normal cooling, the high speed is controlled by Vintage Air Trinary pressure switch. If you need high and low speed from the PCM it will require three relays or possibly blocking diodes so your PCM doesn't see the ground from the AC.

Project GatTagO

iTrader: (7)

What kind of car is this installed in? What is the radiator core size?

Andrew