I have a S-type from 2004 2.7d and have some electrical problems that come and go. It started a few weeks ago with the windscreenwipers going on by them selfves when the selector stalk was in off position. I have the rainsensor.option. Now the windscreen wipers have stopped working completely.
Yesterday the front lights, main beam, dipped lights, indicators and fog lights stopped working. Horn also stopped working. This morning while driving the windscreed wipers started working by it self and then the horn and front lights all started to work again.
Sometimes te remote doorlocking does not work. Other times it works again. Also the interior light does nog come on when opening the car. I have tried to switch it back on. Sometimes that works and then goes off again. The car is fitted with a factory alarm
I replaced the main car battery yesterday hoping that that would help but that has had not much effect.
Yesterday the oil light came on after starting when the car was warm and at the same the steering was heavy. Oil light went off and steering was back to normal.

The car drives excellent. I am suspecting the general electronic control module, bad wiring.
Has anybody any ideas?

 

When you replaced the battery, did you check and clean the grounding point where the negative cable bolts to the car's chassis...?

While you ponder this, you might also want to indicate your general location in your profile and post the expected "intro" in the New Member's forum, here:

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Not sure about the oil light, but the heavy steering could be caused by a slipping serpentine belt. If the belt was not getting a good grip on each pulley, the alternator would also not be spinning at full speed. That would in turn cause poor charging, and the resultant low voltage could be responsible for the other electrical gremlins.

The first thing I'd suggest is charging the battery to be sure of a full charge. Batteries typically are not fully charged at the time of sale. I highly suggest an automatic charger with at least a 10 amp output. Don't waste your time with a trickle charger, it won't do the job. With the battery fully charged, see if the symptoms get better. If so, you're probably looking at a problem with the charging system, or something is running the battery down excessively between drives.

These cars, especially 2003+, are VERY finicky about the prestart voltage. From forum experience, 12.6V or higher is what you need to see. That is a VERY high standard. Don't judge the battery state-of-charge by how fast the starter cranks. This isn't like an old Vauxhall. Before proceeding, please make sure the battery is fully charged and reads 12.6V or higher prestart.

It's easy to check the charging system with a voltmeter on the battery terminals. 2003+ cars have a smart charging system, that runs around 14.5V after engine start, slowly tapering off to around 13.5V after several minutes.

 

Thank you for the advice. I have charged the battery to full. The problems are still there. I think it is the front electronic module that is faulty. I have orderd one on ebay. See if that solves the problems.

 

Go look at a schematic. All those things come from the steering column. Might be a common ground thats intermittent. Or the Connector is loose or corroded or burnt. I had an Oldsmobile once that had a multifunction switch that controlled the lights cruise control turn signals etc. and over time the metal inside that switch on the column would wear down the contacts and the little pieces of metal from the contacts would stick in the dielectric grease inside the switch and eventually it would short out and make your lights flash on and off randomly so that’s something to think about also

 

Any progress?

I'm leaning towards a bad control switch in the column, too.

IIRC (sorry, no access to the wiring diagrams at the moment), the multi-function control switch uses a group of internal resistors. This cuts down on external wiring within the cramped confines of the steering column. Only a handful of wires are needed, not dozens

The corresponding control module reads the resistance value from the switch and interprets that as a command. Just a guess on details, but maybe it's something like 100 ohms = low beams, 200 ohms = high beams, 300 ohms = left turn, etc. See a potential for trouble there? Throw in a little extra resistance from worn or dirty contacts inside the switch, and now the poor control module seems like it has a mind of its own.

i know the radio control buttons on the steering wheel use this arrangement. On my '02, sometimes when I try to adjust the volume, I end up changing stations instead. I'm too lazy to clean or replace the switch pack. I bet you're running into a similar problem with your control switch.

 

Thank you for your idea's. I will have a good look at them. At the moment I have removed the wiper stalk. The wipers have not moved since. That suggests that the stalk is faulty. I have orderd an used one on Ebay. It will arrive soon. After a couple of trips the front lights, horn and indicators have started to work again. I don't know for how long though. Interior lights still don't come on.
I have also ordered a front electronic module from the same car, type and year and matching numbers. That should be here next week.

Regards,
Philip

 

I replaced the wiper stalk. Wipers still didnt work. Today I replaced the used front electronic module with a used one from the same year, same engine and partnummer. I have a left hand drive and it is located on the left in the footwell. A bit difficult to get to but it is plug and play. I disconnected the battery first. After connecting everything. I started the car. It was a very nice to see everything worked again. Windscreen wipers work again, front lights and indicators work again, interior lights work , horn works again, no oil warning light and heavy steering, remote control works again. Hopefully this has fixed it for good.

 

Groovy, glad to hear you got everything resolved. And a very big thank you for coming back to update the thread with the fix.

No doubt the wiper stalk was the actual fix, followed by a top secret self-calibration process that coincidentally finished at the same time you replaced the front electronic module. This is the only plausible explanation, because otherwise this meant I was wrong less correct than usual. As we all know, this is impossible, and would lead to unforeseen consequences such as the Earth shifting from its axis, earthquakes, tsunamis, rioting, a new Justin Bieber album, etc.