1N4001 trouble

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my0wn3ds
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1N4001 trouble

Post by my0wn3ds »

I almost finished my MS-II v3.0
Engine Ford 5.0 code F, 1987, no MAF in stock

I have found the same post with answer, but not clearly understood it.

Q:
i'm sorry, i'm still very confused as to were i need to add this diode.. can anyone help?
A:
The best location is in the wiring harness itself, right at the IAC valve.
Assembling Guide:
You will also have to put a 1N4001 diode across the PWM Idle valve itself - the banded end goes to the 12 Volt supply, the non-banded end goes to the lead that goes to MegaSquirt (this diode is for flyback purposes on the idle valve)
Can anyone put this diode on this scheme?
http://www.DIYAutoTune.com/images/carte ... wiring.gif

Thanks and sorry for bad english)
94'Mustang 302 swap/4BBL, 87'Cougar XR-7 289 swap/turbo project
DonTZ125
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Re: 1N4001 trouble

Post by DonTZ125 »

Like you quoted - right at the valve itself. The +12v supply is the orange lead to the valve; connect the banded end of the diode to the +12v pin of the valve. The non-banded end goes to the ground pin on the valve, connected to the yellow lead going back to the MS.
Heribert
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Re: 1N4001 trouble

Post by Heribert »

My US$ 0,02´s worth, to be sure.
Hook everything up as per schematic . To positively identify the battery supply wire going to the PWM valve, unplug the valve and switch on the ignition.
Use a Voltmeter or simply a 12 V 5 W bulb. Connect one end of this to the chassis Probe the plug , the pin that gives you 12 V /where the lamp goes on is the +12V supply wire. Connect the banded end of the diode to this wire and the other end of the diode to the other wire in the PWM lead pair.
A bit of shrink tubing over the diode/wires will make it unobtrusive and nice!

Heribert
If it is not understood , it will not work!
my0wn3ds
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Re: 1N4001 trouble

Post by my0wn3ds »

OK, i see)

Like on image below?

Image
94'Mustang 302 swap/4BBL, 87'Cougar XR-7 289 swap/turbo project
DonTZ125
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Re: 1N4001 trouble

Post by DonTZ125 »

That's it! Like Heribert said, be REAL sure you have the +12v and GND wires properly identified, or else you're basically installing a short circuit.
my0wn3ds
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Re: 1N4001 trouble

Post by my0wn3ds »

OK, got it :yeah!:
Thanks!
94'Mustang 302 swap/4BBL, 87'Cougar XR-7 289 swap/turbo project
my0wn3ds
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Re: 1N4001 trouble

Post by my0wn3ds »

I have stock diode on my Idle speed solenoid.
Will it work with MS?
94'Mustang 302 swap/4BBL, 87'Cougar XR-7 289 swap/turbo project
Heribert
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Re: 1N4001 trouble

Post by Heribert »

Yes, it will.
Just make sure that you get the polarity right, the schematic in this thread says it all.

Best regards

Heribert
If it is not understood , it will not work!
my0wn3ds
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Re: 1N4001 trouble

Post by my0wn3ds »

Anyway my Idle solenoid doesn't work... with stock diode or with 1N4001...

I'll try to replace it.
94'Mustang 302 swap/4BBL, 87'Cougar XR-7 289 swap/turbo project
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