Hi, new member here. I have a 52 plate Focus 1.8, and up until Monday morning has been performing as faultless as it can be, however Monday morning saw :-

No interior light, no indicators, no heated windscreen/rear screen, no rear wiper, no central locking (don't have remote c/l)
However, lights work, radio works, AC works (well lights up), all dash lights seem to work

I've checked all fuses, even the hateful 63 and found all to be in good working order, I have swapped relays round to rule those out, I have checked all the door switched incase one was 'thinking' it was already locked and all are fine. All wiring I can see seems to be in good health
I will also mention the radio will sometimes give woeful signal issues (suspect earthing fault)

I am no electrician, and have spent many hours today trying everything I can from googling it to death.

If anyone can provide any pointers I would be most grateful

Many thanks

What about front wipers?

That list sounds a bit like the range of stuff controlled by the GEM, which is part of the Passenger side fuse box (aka PJB).

There are a couple (or 3) of big connectors just in front of the front passenger door, hidden under the trim panel. The panel starts in the middle of the door sill, and goes up toward the glovebox. It just unclips (after pulling out a bit of the door rubber seal). Check these are mated ok, and not all green and corroded inside. Also check the wiring connectors to the PJB.

The GEM is a major electronic module, and has diagnostic facilities & self test facilities. To access these you need a Modified ELM327 & Forscan. Or go to a garage and get a £100 bill before they do anything!

 You will find a lot about ELM327 & Forscan on this site, which together provide a very comprehensive diagnosis & maintenance tool.

For ELM327 see:

http://www.spanglefish.com/TunnelratElectronics/index.asp?pageid=516992

One of these will pay for itself in no time.

you ill also need a program called Forscan, its free and you can get it from

http://forscan.org/download.html

 

Switch stuff on give the connectors a good wiggle and see if anything changes. That might give you a big clue as to where the problem lies. Turn off and disconnect the battery try plugging things in and out giving the connector surfaces a spray with contact cleaner and see if that helps. Beyond that you may be on to the expensive stuff...

Oh also look out for damaged/corroded earth connections particular. 

 

Hi guys, thanks for the replies. Front wipers are fine, I'm thinking it's a grounding problem somewhere, got a friend going to give a it a look over with a multimeter, will try disconnecting the battery, thanks muchly

I just noticed you have the mk1 Focus, I only have the Mk2 wiring diagram. That is 132 A2 pages, takes a bit of getting around, but then that is part of my day job.

I have just asked Preee (who supplied the diag) if he knows of a mk1 diagram.

I still suspect the GEM in the PJB is the common link, but there might just be a relay or fuse in the engine fuse box (FJB) that is common to all the failed bits, on your car. If you have a Haynes, then there will be a very much simplified diagram in there.

Peter.

 

Thanks Peter, I've checked all the fuses, someone else mentioned it could be a relay. I'm going to disconnect the battery as suggested by BOF. I've also just found a GEM testing procedure, so am off to give that a go.

*Update, found the test procedure here -> http://mr-fix.info/ford-focus-mk1-hidden-menu/
Steps 18 and 19 showed Ab-H & Eb-H respectively. So some serious googling is in order today

13 hours ago, Andyb7274 said:

Steps 18 and 19 showed Ab-H & Eb-H respectively.

Did step 6, DTCs show anything? (The test you ran was not a GEM test, it was an IC test).

If you done any serious Googling yet, you will see that EBD seems to be Electronic Brake Distribution. I don't know what that is, but it must surely take place in the ABS module. And that is the other fail. This seems a bit strange.

CAN buses are digital links, a bit but not much, like USB. The Mk2 has two of these. One goes from the IC (Instrument Cluster), via ABS & other underbonnet modules, to the PCM (Engine Computer). The other goes from IC via various body modules (like door modules) to the GEM in the Passenger Fuse box. The IC is thus a vital link between all parts of the car. CAN bus faults, and IC faults can cause all sorts of very confusing & complex errors, often with false reporting of faulty modules, because the bits can't talk to each other.

I do not yet know whether the Mk1 has two CAN buses, or one. I half suspected a CAN bus problem at the start, it seemed the most likely link between the faults you described.

I think you really could do with a full diagnostic check. I believe that the ELM & Forscan system in my 1st post is compatible with the Mk1. Certainly worth a try.

On a Mk2, I would say an IC fault is indicated, as this is the only link between the ABS (& EBD) and the GEM, and the symtoms you listed.

If a Mk1 has one CAN bus, then it is less clear. This would put the ABS ( with its reported errors), the IC (running the test) and the GEM (driving the failed circuits), on the same bus, with no obvious culprit.

I do not think an earth error could directly cause this range of symptoms, but bad earth connections, bad CAN bus connections, or duff batteries for that matter, could upset one of those electronic modules. Did your mate with the DVM check the battery?

Sorry if this sounds confusing, but I am guessing (educated guesses, I am an electronic engineer, but still guesses), and thinking on my feet!

Check the battery (if not already done), and see if you can get a diagnostic check. If anyone else reading this has more mk1 experience, then please say.

 

 

 

 

 

gem module or gem module connectors /wiring corroded, assuming you have checked all the fuses correctly.

After some more testing and finding a link on another forum, it's looking like it's the Body Control Module at fault. I can live without the central locking, intermittent wipers, but I miss the indicators 

Apparently I just need to get a BCM with similar serial and it doesn't need recoding, appreciate any input/advice on this

Many thanks for all feedback/advice so far

I think BCM is another (less manufacturer specific) name for GEM.

From http://www.knowyourparts.com/technical-articles/more-modules-than-you-can-shake-a-stick-at/

"The Body Control Module (BCM) is yet another major module that usually handles multiple tasks ranging from lighting and other electrical accessories to climate control, keyless entry, anti-theft duties and managing communications between other modules. The functions can vary greatly depending on the year, make and model of vehicle, and even its list of options.

This brings us to the “other” modules.  These modules aren’t very well known and most people don’t know about them until one fails and they have to get it replaced. These modules have all kinds of strange and confusing acronyms as each carmaker has come up with its own unique list of acronyms for the various modules they use in their vehicles.

A Real Gem
A typical example is a Ford GEM module (Generic Electronic Module). Ford started using these in the mid-to-late 1990s in various cars, minivans and light trucks. It is essentially a body control module it terms of what it actually does, though the list of control functions will vary depending on the vehicle application and its options. Some of the control functions include interior lighting, daytime running lamps, power windows, warning chimes and lamps, rear window defroster, windshield wipers and washers, perimeter anti-theft alarm, remote keyless entry and battery saver functions. The module may be located behind the fuse panel under the dash (Ford F-series trucks) or in the engine compartment near the power center.

If a Ford GEM module has to be replaced (which can happen if water infiltrates and corrodes the electronics inside the black box), it usually requires a part number that is specific to the customer’s vehicle. To further complicate matters, Ford says their GEM modules need to be programmed after they have been installed so they will function correctly. But some are simply plug-n’-play and will work right out of the box.
Many modules on many different makes and models of vehicles do require either reprogramming for a specific vehicle application or VIN code, or have to undergo some type of initialization or learning procedure (which may require a scan tool) after they have been installed before they will function normally. If a DIY customer doesn’t know this, they may think the replacement module you sold them is no good and bring it back with a warranty claim."

The comments about the need, or not, to reprogram for the vehicle are interesting, if somewhat confusing.

Do double check wiring, connectors, earths & battery before shelling out for a new, or 2nd hand BCM/GEM. A 2nd hand one may still need setting up to work. Forscan, or one of the other downloadable packages, may be able to do this, otherwise it may be an expensive garage or auto-electrician job.

Hopefully yours will not need setting up. Please post any results here, so others can learn, and maybe help.

 

 

Early focus modules were known as timer control module, then gem , and now mk2 onwards bcm.

All fixed, had it in the garage yesterday getting the earths checked and found all to be sound. GEM/BCM unit replaced for £12 from scrapyard, everything working again, thank you to all who provided advice.

For reference it was a plug in and go, no reprogramming required.

7 hours ago, Andyb7274 said:

GEM/BCM unit replaced for £12 from scrapyard, everything working again, thank you to all who provided advice.

For reference it was a plug in and go, no reprogramming required.

Sounds a really good fix! Great news

Electrician can replace GEM/BCM unit or not ?