Volvo v50 / Ford Focus ECM /ECU connection problems. 

Tip: ALWAYS keep the bottom engine bay cover, ECU/ECM covers, etc. All cars I've had with severe electrical issues on ECU's, etc. were always due to the lack of the bottom cover! Previous owners removed them. Usually people do that to facilitate oil and filter changes. Over time water splashing, found it's way into the terminals. On the worst case scenario I've had, they corroded to the point of breaking off! Not good at all. A royal pain the a__ to solve. I did solve it but it's not fun! Tip 2: Use a dremel type tool equiped with a small steel or brass rotating brush. Fast and very effective way to clean relays, battery or fuse terminals. In a jiffy you get bright and shiny clean metal contacts.

Thanks for the video, I just had my Volvo V50 T5 2007 fixed today before seeing this, gremlins were messing with DIM/Wiper/TCM/ECM/CEM/BCM... for sure, cleaning CEM fixes the problem for most of the time, but I found the problems are also come from steering wheel clockspring (SWM), and accelerate pedal, YES THEY ARE, mostly from SWM, when checking DTC code with VIDA there are many error codes related to SWM, and also the modules rely on SWM signal. Some from my own experience to diagnose problem are the following. 1. when scary messages come up, like DSTC error, blis error, brake system error, disconnect the battery for like 15 minutes or longer, best charge up the battery to full before reconnection. 2. if the messages gone, drive on the road and see if the message comes back, if they are, that could means SWM is generating wrong signal/messing with CANBUS connection, try to replace the steering wheel clockspring. 3. clean up CEM like the video instruction. Hope my experience helps, there is clockspring made by NTY, it's a cheaper option than expensive geniune Volvo one, haven't try before if someone could share their experience that will be great.

Good informative video with excellent lighting. Thank you and sorry for your loss. We lost our big boy Duke (a bordeaux) 5 years ago now and still think of him daily

Good video, many thanks. Sorry about the loss of your big old boy.

I have a Volvo V50 2 LT diesel thanks for this very interesting video I'm not a moto engineer but a production engineer where my experience is with P L C's and other electronics you struggle putting gloves on put some talcum power in them, it makes them much easier to get them on and off. If you use an electric toothbrush don't throw the old brush head away it makes a great cleaning gadget in hard to get places. Really sorry you lost you 4 legged friend. Best wishes from the UK

Excellent video, thank you! Very sorry about your dog.

Such videos deserve... my gratitude. Thank you man.

excellent video, thank you for the viddeos on this car

Thank You for a useful video, I just got a V50 1.6 td. Sorry about your dog my friend.

Had mad electrical gremlins and angry pixies with my 2007 V50 T5. It was completely fixed by removing the CEM, and spraying down BOTH the pins in the unit AND the contacts in the plugs with electrical contact cleaner. Never had a problem after that.

I know this phenomenon from my car (PSA, probably same as Volvo) and believe it has got a completely different reason. The Engine Control Unit is a real time computer application, i.e. certain things e.g. fuel injection, ignition must happen at certain times and after 2 crank shaft revolutions everything starts all over again. An ECU which remained the same for some generations of the engine, which may have added sensors and actuators and require addl‘l code in the ECU to service them, runs out of time to work additional instruction. This becomes critical when an engine error occurs. E.g. an EGR valve which is blocked may urge the ECU to repeatedly poll a sensor and try to reposition the EGR valve, also inactivate the climate compressor to keep the engine running and resolve the problem. These add‘l commands require the ECU to deprioritise other work which would normally be done, e.g. calculate certain parameters and publish them on the CAN-Bus for other control units. In my car e.g. the oil pressure is not being published anymore, consequently the cluster controller sends a oil pressure warning to the dash. Many other control units complain about a lost connection with the ECU. The ABS controller inactivates ASR and ESP, because both programs need to influence the engine acceleration and cannot work if the ECU does not respond anymore. I had different engine problems in my car and the error sequence in various control units was exactly the same. Long story short: check the error in the ECU, that‘s the root cause!

using your instruction i pulled out the CEM and cleaned all terminals and plugs with contact60 spray and compressed air. I swear i feel the engine reacted quicker than it did before. Still got the abs/anti skid message, but at least the issue with wipers going on/off and engine switching off seems to be solved.. for now

11:45 The drain hole is clogged. Clean it and the water will drain perfectly well. It's faster to do, than to write about it. ;-) Sorry for your doggie 😞

Danku voor het video! İk heb Volvo S40 2010. İk ok zo af het Cem module en proper maken . Danku

Prayers for Doggy 🙏👍

About 6 months ago I noticed the radio would cut out, when I shut the car off the key would get stuck half way with no lights on dash on and I couldn’t remove the key. if I opened the door, or the hood the everything would start working again. Sometimes I’d have to wait longer. I cleaned the ecm. But now this morning I am having similar problems. Could it be the ecm again?

👍

The CEM in Volvos is basically the gateway module. I had most of my electrics fail in my 2003 XC90 fail after 3 hours of driving. I got the DEM repaired (the cause of my "anti-skid service required" error message) to make sure that it wasn't causing the CEM to throw a wobbly. The problem came back on a long journey so I got the CEM removed (easier on a LHD V50 than a RHD XC90) and sent it off for repair. It has been fine for now but the real test will be the next long journey I undertake.

Volvo has some issues with the windscreen sealing. On some models water gets inside and in this case it might explain why the connections were corroded.

Where have u get the small Fuses , i need all of them

What is that OBD reader? I need one

Hi, I have V50 2006, 2D, problem is that all right side doors and windows locked and not working, maybe you have idea what is wrong?..any similar expierence?

My c30 1.6d would run fine then just cut out then start again 15 mins later it was the crankshaft position sensor

That is the CEM not the ECM.. the ECM are located besides the battery on 1.8L engine.

One thing can i tell here, smal animal can tip over big cargo...

worst car i ever had.. never gonna buy another vovlo