Hi guys, this is my first posting here. To be honest, I don't know much about cars and am at the edge about my Ford Focus problem. Hopefully, someone can help me here. I can't afford to spend more money into it. The problem description is as follows:

Car won't start and immobiliser lights flashing. Engine won't even turn. I have changed the key fob battery a week before this incident because the car alarm would go off randomly at night. Exactly a week after, the car just suddenly showed engine malfunction sign with the immobiliser light flashing fast. After the incident, I have tried the following steps: 1. to reprogram the car key by inserting the key into the ignition and turning it on four times until there is a beep (it did, and I pressed the unlock button with a following beep), 2. inserting the key to the driver's door, turning it and leaving it for 1 minute before unlocking the door, 3. disconnecting the car battery terminal overnight before connecting it and trying to start. None of it worked.  The LED lights still kept on flashing fast. I have done self-diagnostics and the car gave DTC codes D900, E510 and D147. The RAC then came and used his scanner and gave more detailed codes P1662 (immobiliser ID does not match), U0140 (loss communication with body control module) and P1662 (theft detected). The engine wouldn't even turn, but the RAC confirmed that the car battery is fine. So, he said it's the immobiliser or key not talking to each other correctly.  Today, a car locksmith came, made a new key, and reprogrammed the immobiliser and everything worked out fine. Car started and I was able to drive the car home. However, a few hours later, the problem came back again as I started the car. It was fine when I started the car but as soon as I switched on the headlights, the car gave the same previous warnings (engine malfunction, power steering malfunction). Now, I couldn't start the car anymore. Same issue returned. The locksmith mentioned to me that it's likely the immobiliser problem and only Ford can fix it. Please help me as soon as possible. Really on the edge here Tany thanks and apologies if any of my description is unclear.

Is It mk2.5 ?  Common problem with cracked soldering in the instrument cluster or bad connection on canbus connectors.  My brother had this problem.  Rac told him he needed to have Keys reprogrammed . Luckily we didn’t waste money on that as it’s not that. Plenty of threads on here about this problem. YouTube has videos on how to repair the soldering. 

This is where I detailed the problem on my brothers car.  Hopefully yours does not need such drastic work  but there is some useful info in there about where connectors are etc. and checking with an ohmeter. but soldering on instrument cluster is most likely.

 

Hi many thanks for your reply. Did your brother's car have the same symptom? I am not sure which is MK2.5? My car is a Ford Focus 1.8 TDCI. How much did it cost him btw?

This is mk2.5. 

yes same symptoms. One of you error codes starts with u which is typical of faulty connections. It didn’t cost my brother anything to fix it as I did all the work. Which was not enjoyable but I didn’t want to let the car beat me.  And my brother didn’t have any money. 

In this situation most people remove the instrument cluster which is a ten minute job with a screwdriver and send it off to be resoldered. There are many companies offering the service as it’s a common problem.  I don’t know the cost.  There is no guarantee that is the problem , but it is quite likely. 

In case you wonder why the soldering needs redoing.  Years ago solder had lead in it.  Then for environmental reasons the lead ingredient was banned.  This means the solder is more brittle.  Lead is still allowed for some uses like aviation and spacecraft where reliability is more critical to safety. But not cars.  

If dtcs are appearing from what looks like unrelated modules, it points toward can bus   connections either in the instrument cluster or at the plugs to the fuse box behind the glove box if exposed to water from the windscreen.  Cluster repairs/reconditioning usually cost around £100  as was the case with my son’s 2008 ST.

whacking the dash above the cluster can exhibit faulty solder joints there.

Hi! many thanks for the replies! highly appreciate it!

Isetta - That is something I could probably do (or not) or send to a garage. Similar to your brother, I also don't have the money 😅. I read your previous thread, I have to say, that was some intensive and extensive work done. Mine is 1.8 diesel which has a Duratorq on the engine cover. 

RL123 - I checked the fuse box behind the glove box or should I say, located just above the passenger's leg area. I did not feel any water or moisture from the fuse box. My instrument cluster did not show any weird signs on its screen however, is this a valid observation for instrument cluster fault? Also, it has been wet recently in Coventry and my windscreen have condensation in the inner part. 

This leads me to two questions; 1. if I manage to fix the IC, how do I prevent from recurring water exposure? 2. After IC fix, do the codes need to be cleared before the car is able to be started?

Hi everyone, just an update. Still no good news. Today, a tech/mechanic from a car electronics company came to try fix my IC. The deal was if he could fix the issue, payment will be 150 GBP. If not, no payment. 

So, the guy came, took off the IC and worked on it in his van. Few moments later, he came out, attached it to the main connector but still the same. He then tried to jumpstart the car, used an ohmmeter to measure resistance in the engine fusebox, took off some fuses and reinserted them. None worked.

In the end, he said it was the ECU/BCM burnt. He said while the problem was still going on, the attempts to start it sent electrical currents to the ECU and burnt it. I then countered why did the locksmith managed to start the car a week after the problem if it was the ECU burnt. I even drove around and park my car at Tesco. It was only later in the evening, after 5 minutes of warming up the car and as soon as I turned on the headlights, the engine malfunction warning came on. Then, I tried to restart it, it wouldn't work. I did apologise for my disagreement because I didn't mean any bad intents or try to question his experience. Just super stressed about this...

He did say that he made repairs to my IC so I assume that eliminates the IC?...

Any thoughts please...

A few minutes would not be enough time to disassemble the Custer and fix solder joints. I would expect 30 mins min if work done. My son’s 2008 ST had limp home, engine malfunction, and power steering error. Took out the ic ,£96 to repair .

have yet to clear the codes but runs fine with no problems.

fuse box plugs have been known to get green corrosion when wet some have reported

 

 

Hi, sorry he did work on it for about half an hour or so. My bad on that. The fuse box was fine, no moisture or corrosion as far as I can tell. The technician didn't mention anything about that either.  

My error is the same as your son's.

Apologies if this has been answered, but I now know how to take out the IC. Is there any other way to diagnose an IC problem? 

Ford just got back and said that I need to arrange a recovery of my car to them for an initial diagnosis of 70 GBP. I am thinking about it, but I have had three technician/mechanics come and can't afford to spend money on more diagnosis without actual fix.

I don't mean to sound like a newbie but my knowledge on car fixes is basic at best. Sorry.

My son’s car is a 2.5 petrol , not diesel just for the record. A whack on the dash above the cluster was enough to shock it out of limp mode. Our local repairer checked it for £35 and checking and repair was £96. That was 18 months ago.

I do wonder if he did the instrument cluster properly, to do it properly needs a lot of dismantling of it, like all the needles have to be removed from all the gauges to fully remove the circuit board to get to where the connected pins need soldering.    In the link I gave to all the stuff I did on my brothers focus it talks about using an ohmeter on the obd socket to check if there is a break in canbus between the socket and cluster or between socket and ecu. 

I wonder that too actually. Because after his fix on the IC failed to fix the issue, he looked puzzled. I am no way knowledgeable on car electronics, but I did half-heartedly expect some computer diagnostics or checking the ECU etc. instead of just using ohmeter on individual fuses. Also, I still don't agree with his 'ECU is damaged' conclusion. Despite that, I try to give him the benefit of the doubt and will include his assessment and work in describing the whole problem. I am still looking for reliable car electronic mechanic around my area which can identify the actual fault rather than possibilities. Did contact someone but got told off because he said I contacted the wrong companies and now wants him to fix it for free until the car is running, which is untrue. I explained it extensively and hopes he understands the situation. Having a car can be a hard life... Anyways, am still looking and will update what it is for anyone's need in the future.

Mine sufferered from this issue. Got the dials re-soldered from a chap on eBay, must’ve been £100. No issue at all afterwards. 
 

right PITA to finally identify what was wrong with it, I too went down immobiliser route with no success.

Search ebay for Focus MK2 instrument cluster repair, choose the one you want, remove your cluster:

Pull up the upper steering column cover

Remove x2 screws from cluster

place thin blade at top/centre of cluster to release clip

remove cluster

disconnect

Send cluster off to be repaired