Air Condition Idle up with 2-speed fan (MSPNP Gen 2 V1.2)

93CobraUSAF

New Member
Sep 14, 2019
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Maine
Greetings to all,

As titled, I am currently running the MSPNP Gen2 with V1.2 (older version with minimum outputs).

I've recently moved to a hotter climate area that requires me to use A/C.

As mentioned, I have the older version of the MSPNP Gen 2 with required me to disable the pin 85 from the WOT relay.

Currently and independantly, I'm running a 2-speed fan (Mark VIII, Thunderbird) using a Volvo 2-speed controller and a BMW sensor (low/high) with a relay to control the A/C.

I would like to have the MS control the fan speed because as of now, when I turn on the A/C, it puts a load on the engine whereby the RPMS dip to the point where it wants to/and dies (basically, the idle does not ramp up to compensate for the additional load, and therefore the engine wants to die).

From my understand, the MS V1.2 has additional output controls (2-5) that I can program. I could figure out to set up the low and high speeds, but my question is "how toprogram to compensate for the additional load when I turn on the A/C?"
 
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Pin 10 of the stock ECU has a 12v+ trigger when the AC is on. The ms2pnp (not sure about your version) has this input wired to tableswitch input through a transistor to protect the input. You should be able to setup the AC idle up function.

Do some looking and get back to me. This has no affect on the wot relay but we could incorporate that back in using one of the outputs you have available.
 
Thanks for the quick response....

I did some looking around, and here's where I'm at. I apologize for my ignorance up front....

Now, are you saying that I can connect pin 10 to the Table Switch Output (pin 12) on the MS2PNP? Or will I have to run a relay?

Based on diyautotune's website concerning the MS2PNP Gen 2:

1588532520372.png

1588532129762.png




As for setting up the 2-speed fan, does this look correct? For the high speed, I also want to enable it when I turn the A/C on...how do I set this up? or can I?

1588533116105.png
1588533366130.png



Thanks in advance.
 
...

I would like to have the MS control the fan speed because as of now, when I turn on the A/C, it puts a load on the engine whereby the RPMS dip to the point where it wants to/and dies (basically, the idle does not ramp up to compensate for the additional load, and therefore the engine wants to die).

From my understand, the MS V1.2 has additional output controls (2-5) that I can program. I could figure out to set up the low and high speeds, but my question is "how to program to compensate for the additional load when I turn on the A/C?"
Only a soft start PWM controller will fix that. You then don't need the high & low speeds terminals on the Mark VIII.
The WOT & A/C idle up can be controlled by the MS, independent of the controller.