Skip to content
View in the app

A better way to browse. Learn more.
Ford Owners Club - Ford Forums

A full-screen app on your home screen with push notifications, badges and more.

To install this app on iOS and iPadOS
  1. Tap the Share icon in Safari
  2. Scroll the menu and tap Add to Home Screen.
  3. Tap Add in the top-right corner.
To install this app on Android
  1. Tap the 3-dot menu (⋮) in the top-right corner of the browser.
  2. Tap Add to Home screen or Install app.
  3. Confirm by tapping Install.



Join the Independent Ford Owners' Club

Our community has been built by enthusiasts, for enthusiasts, and proudly run by Ford owners' for over 18 years. As an independent, non-official club, everything you’ll find here, advice, support, and opinions, comes directly from members with genuine Ford ownership experience.

Join our friendly community... it's Free!

 

5V reference wiring diagram

nver
nver
in Ford Fiesta Club

Featured Replies

Hi

Can anyone please share 5V reference circuit 'C' wiring diagram for 2009 Ford Fiesta 1.6 TDCi ?

My problem:

The car is not starting and got DTC P0698 with MIL light on the dashboard.  I checked the 5V VREF at EGR valve connector PIN1 and multimeter is reading 0.25V  which seems like the real issue. Very intermittently this goes back to 4.9/5V and then car starts.

I tried a new EGR but didn't fix the problem, also I disconnected harrness from EGR and still 0.25V on PIN 1. So looks like EGR is OK.

What I would like to try is to disconnect other sensors on the same 5V bus to confirm which is bad (if its a sensor issue at all ). For this reason I need the wiring diagrams please.

Any other suggestion is also welcome.

Many thanks

  • Quote
    • Sad 1


    Is that reference the source? Anything sinking the reference current to that extent will be obvious once disconnected. Go round the engine bay and pull the connectors one at a time then replace them as you go. There will not be more than a dozen.  You do not need a diagram. Just keep checking the voltage until you find the short. Give each connector a good wiggle as you go. It could be short inside the wiring.

  • Quote

    • Latest Deals

    Ford UK Shop for genuine Ford parts & accessories

    Disclaimer: As the club is an eBay Partner, The club may be compensated if you make a purchase via the club

    Join the conversation

    You can post now and register later. If you have an account, sign in now to post with your account.

    Guest
    Reply to this topic...
    Go to topic listing

    The "Digestive"

    • The Digestive Forum Roundup (24th May - 31st May 2026)

      Steve ·
      The Digestive Forum Roundup (24th May - 31st May 2026) We hope this email finds you well and enjoying your week. As always, our forum has been buzzing with activity, so we’ve compiled the highlights for you. Plenty of interesting discussions are taking place, especially around the Ford Focus and Fiesta models. Starting off with the Focus, many members have been discussing issues with the Emergency Call System, particularly in the Mk4 model. PLB raised concerns about persistent malfunctions, a se
      Steve
      Steve
      • 233 views





    Background Picker
    Customize Layout

    Account

    Navigation

    Search

    Search

    Configure browser push notifications
    Chrome (Android)
    1. Tap the lock icon next to the address bar.
    2. Tap Permissions → Notifications.
    3. Adjust your preference.
    Chrome (Desktop)
    1. Click the padlock icon in the address bar.
    2. Select Site settings.
    3. Find Notifications and adjust your preference.