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Discussion Starter · #1 ·
I have a 1994 F250 Turbo Diesel (VIN F) that suddenly started running so bad I had to have it towed. The CEL light is on, so I tried to read the codes from the data link test connector under the hood using an analog meter (red hooked to battery + black to pin 4) and jumper wire from pin 2 to test connector. My meter shows battery voltage before I even turn the key. When I turn the key the meter shows 0 volts but does not emit any codes. I tried reversing the leads, but got nothing. I also have an OBD 2 style connector under the dash, but when I plug in my code reader (Blue Point EECR1) I get no code.
Is there a different method used for the 1994 Model? Should I be using the data link under the hood or the OBD-II connector under the dash?
 

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Discussion Starter · #2 ·
Can anyone tell me how to retrieve the error codes? I searched the site and tried all the methods suggested, but got no codes. I tried referencing the OBD manual - still no luck. Is there an adapter I can buy for my Blue Point code reader?
 

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1994 may not be OBD II compliant. IIRC they had to have the PCM flashed. Once that is done the generic code readers don't work on the Powerstroke engines.

You need to verify that it is OBD II compliant and then find a person/shop that has a scanner that can read PSD codes.
 

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The 94's would have originally used the OBDI port under the hood. They had the OBDII port under the dash, but it was inactive. However, over time as the trucks were brought in for servicing, the dealers reflashed many of the PCMs to enable the OBDII for better diagnostics (that's what happened to my 94). Most generic OBDII readers won't read the PSD, but there are readers available (SnapOn MT2500 w/correct module, AutoEnginuity w/Ford Bundle using a laptop). Some will use "this" to monitor parameters. I can't remember if that thread also mentions what additional is needed to read the codes too. Cheers!
 

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That's interesting - I'd never have guessed that the truck would have been built with an inactive connector that could be programmed to become the primary DLC, but it's shown on the 2nd page of this PDF:
http://www.revbase.com/BBBMotor/Wd/DownloadPdf?id=137880

VIP is the old DLC under the hood; generic is OBD-II under the dash.
 

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Discussion Starter · #6 ·
So what your saying is - once the PCM has been re-flashed, the OBDI port under the hood no longer works? In addition, only certain code readers will read the OBDII code from the connector under the dash. Is that correct?
 

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Yes, if the PCM has been reflashed the OBDI port will no longer work. Any code reader will need to be able to read the Ford Enhanced parameters. See my previous post for some options, including a thread that uses Bluetooth and an app on your smartphone. Cheers!
 

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Ford never used OBD-1; that's a GM protocol. The DLC under the hood is called VIP for EEC-IV.
 

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Ford never used OBD-1; that's a GM protocol. The DLC under the hood is called VIP for EEC-IV.

OBD I, II and C.A.N. Are not protocols. Protocol is the specific "language" used to communicate between the PCM and a scan tool.
 

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A "protocol" is a language between ANY electronics; including all the ones on a vehicle, or even the various sections & levels within a PCM. But call it what you want - these trucks don't use OBD-I, and never did. Even with a reflash.
 

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I never said OBD I was used AFTER a flash I did say the OBD II worked after the flash.

If you'd like a history lesson on OBD spend some time searching the Internet for "OBD" known as
On
Board
Data

I have owned and operated my own auto repair business for 40+ yrs and I am very familiar with the evolution of OBD.

Protocol as it applies to OBD (subject of this thread) is the specific language between the PCM and the scan tool.
 

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Actually, OBD is On-Board Diagnostics, and OBD-I was NOT just on GM cars. My '89 Colt, built by Mitsubishi and imported by Chrysler, was OBD-I.
 

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Thanks, I meant Diagnostics not Data. Been working in 100+ heat for the last week.
 

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So then we can all agree that these trucks don't use OBD-1, right? That's what I said in posts #5&8.

And that the correct names for the underhood DLC are VIP or EEC-IV, right?

 

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No, but since you think your right I'll let you continue to believe what you believe and I will know I'm right.
 
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Oh, Mr. On Board Data knows better, now?
 
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