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Potential Error In EVTM
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Potential Error In EVTM
 
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I found what I'm sure is an error in the 1985 EVTM and want to make sure y'all agree.
In the page below you can see that it says that Ckt 640 from the upper right is connected to the power going to the tach as well as the three gauges powered by the instrument voltage regulator. That is not the case, and other EVTMs show it differently. In fact, I've included the 1986 page below the 85 page to prove that. But am I missing something? Should I put the pic with the two red lines I've added on the 85 EVTM page? Is there a better way to show that?  
Gary, AKA "Gary fellow": Profile
Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
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Re: Potential Error In EVTM
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Re: Potential Error In EVTM
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The printed circuit between 1981-1986 is identical, so the 1985 EVTM is definitely in error here.
The printed circuit is different for 1980, but not different where the tach circuit is concerned. That's a pretty big error not to be caught before now. Great job Gary in finding that. 
Truck: 1981 F-150 Explorer / Engine: 300-6 California MCU Feedback System / Trans: T-18 - 4 speed / 2.75 Ford Rear Axle Open Diff.
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Re: Potential Error In EVTM
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Thanks, guys. I found it as I was trying to figure out the C208 pinout for Rene recently and was quite confused when I saw that the IVR output appeared to be connected directly to battery voltage. So I did some checking and discovered that they corrected it in '86.
But in looking back at the other EVTM's I find this: 1984: Doesn't even show the tach as far as I can tell. On the Ignition page it sends a signal out to it (F) and gets one back from it (E), but the tach isn't shown on the gauges page. In fact, in the Index there's an entry for Tachometer but no page #. So no "error" but an omission.1983: The tach shows on Ignition pages 19 & 21 as well as in the Index. But not on the gauges page. So no error.1982: Ditto 19831981: No entry in the Index but the tach is shown on Ignition Pg 21 and not on the Gauge page, so no error.1980: This must have been Ford's first attempt at an EVTM as the whole book is lame. The tach is mentioned in the Index as being on Page 45. It is, but not correctly as it doesn't show power nor ground for 8 cyl going to it, but it does show the feed from the ignition module as well as ground.Anyway, the 1985 EVTM now shows the page below. Agree? 
Gary, AKA "Gary fellow": Profile
Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
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Re: Potential Error In EVTM
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That looks like a good correction.
It also shows the original error so we can keep tract, just incase other literature may have the same or similar error.
Truck: 1981 F-150 Explorer / Engine: 300-6 California MCU Feedback System / Trans: T-18 - 4 speed / 2.75 Ford Rear Axle Open Diff.
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Re: Potential Error In EVTM
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