General wiper stopping 2007 fiat ducato

[jimmybrad]

hi
please can someone help, my 2007 ducato wipers work through all modes untill i revthe engine, the wipers speed up a little the stop, switch off the engine, turn ingnition and the wipers start up again, when the engine is started the same happens, any suggestions.
regards
jimbrad

 

[Anthony489]

Hi

I have attached the schematic for the wipers. They have a main power feed, and logic control signals to and from the body control module. There is also an earth.

Inside the wiper motor casing is a thermal/high current overload switch, which protects the motor in case the arms/blades jam (e.g. frozen to the screen). Sometimes these switches become erratic, especially if the van is parked up for along time. If you tap hard with something onto the motor casing, it sometimes gets them going again, otherwise you need a new motor, or motor plus crank etc mechanism if you want to save on dismantling and swapping bits over.

Also worth checking that the spindles are running freely in their housings, as if they are partly seized and motor is having a hard time its current drain will increase. The extra voltage when the battery is being charged (14 rather than 12) will further increase the wiper current, and that might just be enough to trip the overload switch. Once the current is switched off and it cools down it resets itself.

Before you change the motor, check out the short braided engine to body earth strap, under the air filter canister. If it hasn't been changed, fit a new one. They corrode internally and cannot be cleaned up and re-used. Signs of failure include slow cranking, poor charging and glow plug errors.

 

[nigelvan]

Hi Jimbrad,

I had the same exact problem yesterday and did continue Anthony's original thread with my issues. I have replaced the motor and disassembled the wiper assembly because it was heavily corroded together which probably killed the electronics of the motor.

 

[jimmybrad]

Hi

I have attached the schematic for the wipers. They have a main power feed, and logic control signals to and from the body control module. There is also an earth.

Inside the wiper motor casing is a thermal/high current overload switch, which protects the motor in case the arms/blades jam (e.g. frozen to the screen). Sometimes these switches become erratic, especially if the van is parked up for along time. If you tap hard with something onto the motor casing, it sometimes gets them going again, otherwise you need a new motor, or motor plus crank etc mechanism if you want to save on dismantling and swapping bits over.

Also worth checking that the spindles are running freely in their housings, as if they are partly seized and motor is having a hard time its current drain will increase. The extra voltage when the battery is being charged (14 rather than 12) will further increase the wiper current, and that might just be enough to trip the overload switch. Once the current is switched off and it cools down it resets itself.

Before you change the motor, check out the short braided engine to body earth strap, under the air filter canister. If it hasn't been changed, fit a new one. They corrode internally and cannot be cleaned up and re-used. Signs of failure include slow cranking, poor charging and glow plug errors.

thankyou so much for your replys, ive ordered a new motor so will let you know the outcome
regards
jim bradley

 

[jimmybrad]

hi everyone, tried a new motor but just the same, tried ringing round for an auto electrician but most dont answer the phone, one chap at WG auto electrics was very hepful though he only works on commercial and tractor vehicle so could work on my van, but when i described rge symtoms he said it sounds like the BCM,so im going to remove it and send it away to one of the many companies that repair/replace and re programm them, but can anyone tell me where it is, ive seen one thread that says its under the fuse box in the engine compartment ! thankyou
regards
jim bradley

 

[Communicator]

Before embarking on such an ambitious course of action, have you confirmed that the the supply to the motor is not failing?

There is a special procedure to be followed when disconnectin the battery on x250 and later models.

It is my understanding that the BCM is behind the fusebox in cab. You will be able to find more details in the "x250 Training Manual", which is available in the dowloads section of the forum.

 

[nigelvan]

hi everyone, tried a new motor but just the same, tried ringing round for an auto electrician but most dont answer the phone, one chap at WG auto electrics was very hepful though he only works on commercial and tractor vehicle so could work on my van, but when i described rge symtoms he said it sounds like the BCM,so im going to remove it and send it away to one of the many companies that repair/replace and re programm them, but can anyone tell me where it is, ive seen one thread that says its under the fuse box in the engine compartment ! thankyou
regards
jim bradley

As Communicator mentioned, you can easily check the connector if the correct signals are being sent. pin 1 & 2 should have 12V, other ones signal Interval, Low & High speed with an active LOW, this means 0V on the pin when the corresponding mode is active... Have you checked, with motor arm disconnected, if the wipers move freely and the linkage is not corroded? According to the schematic, the BCM is also responsible for activating the windscreen washer pump, does that still work?

 

[jimmybrad]

hi
tried a brand new mortor without the linkages attathed, worked fine through all mode wash wipe etc blip the throttle and the mortor stopped, switch on off and same senario

 

[nigelvan]

Ok, sounds like the BCM is a possible suspect. Do you notice anything else suspicious? From what I read the BCM also controls A/C, locking, windows, headlights... One thing that could happen when you hit the throttle is a voltage spike caused by the alternator... But otherwise I'm out of ideas.

 

[Anthony489]

Hi

Have you checked/changed the engine to body braided earth strap yet ?

As a temporary check, connect one "jump start" type cable from the engine/gearbox metalwork to the body metalwork, making sure of a good clean connection each end e.g. by wriggling and scraping the jaws of each croc clip. Then try the wipers plus revving test again. If they behave, the finger of suspicion points to a bad earth strap. These corrode internally and cannot be repaired/cleaned.

 

[jimmybrad]

hi Anthony, ive ordered a new earth strap, should be here tomorrow,if that dosnt work could you point me in the direction as to where the BCM is located,one thread said it was under the fuse box in the engine compartment them he was told it wasnt so not sure where to look

 

[jimmybrad]

wont download elearn.

 

[Anthony489]

Hi

The BCM sits immediately behind the under-dash fuse/relay/connection unit. You can just see its bottom edge sticking down, which carries a couple of connectors plus the OBD II diagnostic socket in the centre. The two items mate directly together with a hidden multiway plug/socket combination, so they are usually removed as a pair and then separated on the bench. You will need to remove some plastic trim, several multiway connectors and the fixing bolts.

 

[jimmybrad]

hi
just fitted new earth strap started engine up and engine management light stopped on switched wipers on and they were working even reving engine, switched lights on dip and they lit up then died, main beam ok, switch engine off on light came on but died again as did the wipers, when light were on seemed to get brighter as i reved engine the they died so trying charging battery, could it be the alternator that causing all the woes.engine management light goes off now when starting up

 

[Anthony489]

Hi

This is proving to be a bit of a head scratcher, but the fact that main beam is OK gives a clue. The X250 has two Fuse/Relay/Connection modules, one in the engine bay and one under the dashboard.

The Engine Bay Fuses B001 are mostly for things that are associated with the engine. They include (not a full list):

ABS, Glow Plugs, ECU, Horn, Foglights, Washer Pump, Engine Cooling Fans, Cab Heater Fan, Main Beam

The Under Dash Fuses B002 are mostly for things associated with the body. They include:

Instrument Panel, BCM, Electric Windows, Central Locking, Cigar Lighter, Brake Lights, Reversing Lights, Wipers, Dip Beam

As you have misbehaviour from several "customers" of the under dash fuses B002, I am wondering if there is a problem with the live feed to B002. It is supplied from F71, which is an 80A maxi fuse situated on the small panel on the battery positive terminal. A thick red wire runs from here to B002, where it joins with a nut and bolt. I suggest you check out F71 and the connections at each end of the thick red cable. If there is excessive resistance, as soon as you start to draw appreciable current the voltage will drop down, which may make the BCM play up. I also suggest you check out the 10A fuse F38 in B002, which feeds the BCM, as if it has a poor connection this too could starve the BCM of power. Of course, it could all be fine and the BCM is the culprit, but worth eliminating as a possibility.

Just for completeness, the engine bay fuses B001 are supplied in a similar fashion but from F70, which is a 150A fuse. Another thick red wire runs to B001.

Its normal for lights to be a little brighter when you rev up from idling, as the battery voltage will climb a little when the alternator is charging more. This effect will be more pronounced if the battery is in need of a charge. A check with a voltmeter directly on the battery terminals is the best test. You should see something like 12.5 volts when the battery has been sat unused for a while and nothing is switched on. Once the engine has started, this will climb to something like 14 to 14.5 volts as the alternator does its stuff.

 

[jimmybrad]

thankyou, ill look at suggestions today and get back with results
regards
jim bradley

 

[jimmybrad]

for 5 mins i thought you had cracked it, i cleaned all the plugs connecters etc, started engine, wipers working great in all modes lights on , revved engine still working, left wipers going for 5 mins and kept revving engine all good then they stopped, switched off on they started revved engine ok then stopped, tryed again and was ticking over and the tick over started to increase and battery light came on blipped throttle and engine revs came back down to 800 ish but no confidence that the wipers are fixed.
regards
jim bradley

 

[nigelvan]

Hi Jim, Not sure if this helps: Anthony has so much more experience than me, but here goes:
I had the issue with the earth strap as well. My symptoms were: slow rpm of the starter motor (like if the battery was flat), unstable idle rpm and battery light coming on. The idle rpm would also increase, probably the ECU is trying to get the voltage of the alternator up to level. With the engine running I measured a voltage drop of 1-2 volt between the engine block and the chassis. I solved this permanently by wiring an additional 10mm2 cable between block and chassis. Problem hasn't come back since.

I do have a 30A DC-DC charger charging our leisure battery. Because of bad weather I turned it on yesterday and the idle rpm will be higher when starting up and go back to 800 rpm after a few minutes or a quick rev. Without the charger powered on this won't ever happen and the rpm would be always at 750-800rpm, so in my experience what you describe is definitely alternator/earth strap/battery related.

 

[jimmybrad]

thanks Nigel any suggestions much appriciated, the earth strap i took off looked ok, couldnt see any rot so maybe put that on as well as the new strap, woild it be ok to double up with the new strap of should it have a different location.dont know enough about the BCM but im toying with getting it looked at just to put it out of the picture.really thought Anthonys suggestions had cracked, just cancelled my visit to great langdale due to the possibility of rain so need to get it sorted, struggling to get an auto electrician around where i live to have a look at it.

 

[nigelvan]

My strap also looked replaced when I bought the van, not damaged, corroded or cracked, measured resistance and it seemed fine. It seems the connection points on engine/chassis are the culprit. I can clean it and remount the strap and after 1-2 weeks I would have issues again. This is why I added additional cables...