# ECM not communicating **URL:** \ **Category:** Maintenance/Repairs\ **Tags:** electrical-wiring, diagnostics, ford\ **Created:** [November 1, 2024, 3:50pm UTC](https://community.cartalk.com/t/ecm-not-communicating/197864 "2024-11-01T15:50:05Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![dianiskatomas\_191452](https://avatars.discourse-cdn.com/v4/letter/d/958977/32.png) [@dianiskatomas\_191452](https://community.cartalk.com/u/dianiskatomas_191452)\ **Post date:** [November 1, 2024, 3:50pm UTC](https://community.cartalk.com/t/ecm-not-communicating/197864/1 "2024-11-01T15:50:05Z")
Hi, my ford is doing weird things and PCM or ecm is not communicating properly(when i connect to ecm after few seconds i have to reconnect). At random times relay in engine bay relay of glowplugs starts to click for few seconds and stops. This also occurs when i open or close front doors. When i turn igniton on this relays starts to click always and also the valve air intake is opening and closing without a break. Checked the grounds, the ecm was already changed and nothing changed. I think it could be wiring issue but dont know where to start checking. Any suggestions? Thanks ---
**Author:** ![Mustangman](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/mustangman/32/44130_2.png) [@Mustangman](https://community.cartalk.com/u/Mustangman)\ **Post date:** [November 1, 2024, 4:06pm UTC](https://community.cartalk.com/t/ecm-not-communicating/197864/2 "2024-11-01T16:06:00Z")
So did you chase the comm wires to find the short as I suggested? Did you check for shorted or broken wires at the door as @TwinTurbo suggested? Did you get a wiring diagram for the car as @asemaster suggested? You can post this as many times as you want on this forum but you’ll get the same responders and the same responses! ---
**Author:** ![dianiskatomas\_191452](https://avatars.discourse-cdn.com/v4/letter/d/958977/32.png) [@dianiskatomas\_191452](https://community.cartalk.com/u/dianiskatomas_191452)\ **Post date:** [November 1, 2024, 4:18pm UTC](https://community.cartalk.com/t/ecm-not-communicating/197864/3 "2024-11-01T16:18:07Z")
For your information… I posted this because i discovered new things. If you would read closely this is wrote differently than my last post. Next thing are comm wires at doors. Why would they be bad? When i disconnect the door section it does exaclty same thing. Only manipulating with doors does not trigger it but problem is there exaclty as it was. Wiring diagram was the first thing i searched when problem occured. So yeah i thoroughly go with steps i found on the internet and also mentioned in this forum which iam very grateful for. ---
**Author:** ![TwinTurbo](https://avatars.discourse-cdn.com/v4/letter/t/8baadc/32.png) [@TwinTurbo](https://community.cartalk.com/u/TwinTurbo)\ **Post date:** [November 1, 2024, 4:48pm UTC](https://community.cartalk.com/t/ecm-not-communicating/197864/4 "2024-11-01T16:48:18Z")
> [@dianiskatomas\_191452](#): > > Next thing are comm wires at doors. Why would they be bad? This is the third, separate post on this topic. Read the prior one- > A somewhat common failure mode is when the wires going between the chassis and door fail from repeated bending/flexing. Rather than start a new post each time, you should append to prior post so the entire story is not lost. It’s fragmented enough as it is, losing the prior perspective doesn’t help. ---
**Author:** ![Mustangman](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/mustangman/32/44130_2.png) [@Mustangman](https://community.cartalk.com/u/Mustangman)\ **Post date:** [November 1, 2024, 4:49pm UTC](https://community.cartalk.com/t/ecm-not-communicating/197864/5 "2024-11-01T16:49:31Z")
Your 3 posts read the same and you didn’t answer any of my questions. Instead of a US based forum for a car not sold here maybe this is a better forum for your issues. > **[Ford Mondeo IV, generation #4](https://en.fordclub.eu/sub-model/ford-mondeo-iv-28)** > > The Ford Mondeo Mk IV (third generation), codenamed CD345 was officially unveiled in five-door production form by Ford in late 2006. Based on the EUCD platform developed with Volvo, the platform was the same as that used in the new large MPVsGalaxy... Or maybe here > **[Ford Mondeo Mk4 (2007 - 2013)](https://www.talkford.com/categories/ford-mondeo-mk4-2007-2013.96/?origin=serp_auto)** ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [November 1, 2024, 8:40pm UTC](https://community.cartalk.com/t/ecm-not-communicating/197864/6 "2024-11-01T20:40:15Z")
Is the battery fully charged & in good condition? fyi, the UK magazine _Practical Classics_ has posted several u-tube vdos about restoring an older Ford Mondeo. None are concerned with the problem you are having afaik, but if you want to watch them for general interest, Google practical classics fixing up mondeo. ---
**Author:** ![Nevada\_545](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/nevada_545/32/41232_2.png) [@Nevada\_545](https://community.cartalk.com/u/Nevada_545)\ **Post date:** [November 1, 2024, 10:10pm UTC](https://community.cartalk.com/t/ecm-not-communicating/197864/7 "2024-11-01T22:10:58Z")
> [@dianiskatomas\_191452](#): > > When i disconnect the door section it does exaclty same thing. Depends on the location of the door ajar switch. Some computers “wake up” and engage systems; pumps and actuator motors when the driver’s door is opened. The failure is likely within those systems and not the door ajar wiring. ---
**Author:** ![dianiskatomas\_191452](https://avatars.discourse-cdn.com/v4/letter/d/958977/32.png) [@dianiskatomas\_191452](https://community.cartalk.com/u/dianiskatomas_191452)\ **Post date:** [May 11, 2026, 11:24am UTC](https://community.cartalk.com/t/ecm-not-communicating/197864/8 "2026-05-11T11:24:44Z")
RESOLVED: Finally after many many attempts I got it to work. The whole problem was 1 diesel injector internally shorted to ground. This injector was shorting also the ECM. ---
**Author:** ![davesmopar](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/davesmopar/32/41750_2.png) [@davesmopar](https://community.cartalk.com/u/davesmopar)\ **Post date:** [May 11, 2026, 1:08pm UTC](https://community.cartalk.com/t/ecm-not-communicating/197864/9 "2026-05-11T13:08:09Z")
Thank you for the update… I updated the other 2 threads with a link back to this thread since they are all related to the same issue…