W124 Headlamp wash wipe problem

[John Turner]

Can anyone help? When I turn on the lights on my 1995 W124 300D estate, the washer sprays the headlamps continuously even though the washer on the stalk has not been pressed. Anyone know what is likely to be wrong? I have had to disconnect washer pump and headlamp motors, otherwise reservoir empties.
Thanks
John

 

[jedileeboy]

dude

you need to replace the head lamp washers check if the head lamp wipers work if that also could keep your washers on

 

[Terminator]

I suspect the problem lies with the stalk itself. An electrical problem will show up on a fault code diagnostic test so I would suggest you visit your local Mercedes specialist first before shelling out on replacing components that may not be faulty.

 

[LAMAR]

Its most proberly that one of the headlamp wipers is seized and not turning of the washers.

 

[John Turner]

Many thanks for the replies so far. Suggestions I have had to date include failed relay, poor earth, faulty washer wiper motor, seized wiper and faulty stalk!!
Relay clicks and looks good inside.
I cannot find earth under headlamp - on this model the brown wires all run to an earth on metal above shock absorber support on near side of vehicle. Other earths OK - not sure whether a wire might have a break.
I have taken apart wiper motors - electric motors were wet, and I have cleaned. Offside motor definitely functioned momentarily on reassembly. The wiper spindle was seized in its shaft and I have cleaned and freed this.
I have noticed that very occasionally, the control stalk does operate the windscreen wiper when I turn a sharp corner. Maybe a fault does lies here. Any other ideas / tests before I set off to the dealer!
Thanks
john

 

[tom7035]

Hi John.
Before rushing off to donate to your local dealer, invest in a spraycan of Electrical Contact Cleaner from Hellfords or the like, take out the six s/t screws and take off the fusebox/relay cover. Remove the 2 (or maybe 3) relays thus exposed and liberally spray the terminals and replace them. One of these relays affects the headlamp wipers, intermittent screenwipe and something else I can't remember. While you're at it do the same with all the fuses. It'll only take a few minutes and you might be pleasantly surprised at the result. I would be interested to know what happens.
Cheers, Tom.

 

[Andy Cottrell]

Hi John,

Have just investigated why my headlamp motors did not work. It appears that on my E300D (1994) both the headlamp motor drive and headlamp washer drive signals are sent from pin 30 of Relay D.
It may pay you to remove this relay and see if the symptoms persist.
Hope this may be of help.

 

[John Turner]

Thanks for your responses. I tried a number of things today to no avail. I bought some switch cleaner and sprayed relays, fuses, all pump and headlamp connectors, and cleaned earths. Still same problem. Even with relay removed, headlamp washer sprays continuously when lights on! Result of the day: flat battey!! It seems whenever my bonnet or any other opening on the car is left open, I get a flat battery. All interior lights definitely off, but I suspect Scorpion alarm (even though not activated) draws. I suppose this is another problem.
I now have the added problem of resetting the alarm when my battery is charged. Last time this was a hit and miss affair, with indicators, alarm and immobiler all activating and not stopping!! My alarm instructions (Scorpion 918) give no guidance, and I cannot remember which combination of the two buttons and timing made it work last time! As you may detect, my patience is running low on this one!!!
I will probably buy two new headlamp washer wiper motors (available second hand at reasonable cost ~ £40 ish). I understand that there is a contact in these for the washer, since washer only squirts occasionally and wiper operates continuously when lights are on and washers (for windscreen) are operated by main combined stalk. I think my motors must be faulty, or relay is duff, or combination stalk is duff, or there is still a bad earth, or worse still, a combination of the lot.
Any further suggestions anyone?
Regards
John

 

[LAMAR]

Headlamp motors is the way to go.

 

[JonathanC]

Hi John

I think headlamp washer motor being seized in a position that supplys power to the headlamp washers is most likely. Try unplugging the wiper motors and then trying the windscreen wash with the lights on, if it is the headlamp wipers causing the problem the headlight washers shouldn't work. You'll need to remove the headlamps to do this, but it isn't difficult.

P.S. Euro car parts sell the washer motors for about £62 each.

 

[John Turner]

Thanks, tried this and no spray as you suggest. Suggests wiper motor units are the problem, so I intend to replace these and report back!
Thanks for your responses
John

 

[John Turner]

Headlamp wiper / Blower

I replaced the headlamp wiper motors with salvaged units from Dronesfileds. But, when I turn lights on, fuse 3 blows, even though I have not activated wash wipe. There was a brief squirt before the fuse blew! Unplugging right headlamp motor stops fues blowing when lights turned on. Does any body have any more suggestions?

The blower is also intermittent, occasionally coming on after the car has been running for a while, and never coming on on a second run of the car if engine still hot. The car's service record shows that the blower was replaced 2 years ago by an MB independent specialist at 94,000 miles at a cost of £290 (parts £161, labour £80 and Vat the rest). The car has now done £130,000. Search threads suggest problems with a fuse holder that can expand when hot, or a failing regulator. I have located the fuse (10 amp blade in clear plastic box under black plastic cover behind plastic cover behind battery!), but cannot see a problem. Anybody know anything about this or the blower regulator and how to identify the problem?

Thanks
John

 

[LAMAR]

If the fuse does not blow when the motor is disconnected AND DID NOT BLOW WITH THE OLD MOTOR THEN THE FAULT IS THE NEW MOTOR THAT YOU GOT SECOND HAND, PROPERLY GOT A DEAD SHORT

 

[Andy Cottrell]

John,

Due to being extra busy at work today I had time to investigate the wash/wipe problem further. If I unplugged the passenger side headlight wiper motor, the wash/wipe system still functions. Conversely if I unplug the drivers side headlight wiper the wash/wipe doesn't work.
This suggests that the wash function is controlled from the drivers side headlight wiper motor ( unless, of course, I too have a problem).
Do you have access to a multimeter? If so I can supply some resistance readings for you to compare with those on your car.

Good luck.

 

[John Turner]

Thanks Andy and Lamar,
Yes, the system operates from the drivers wash wipe motor. This one has an extra wire when compared to the passenger unit, which can be seen in the plug which plugs into the headlamp. I have had the same result as you, with passenegr motor only running if drivers side unit connected. I have a multimeter, but I understand that when the washer is operated by the stalk on the steering column, only a short pulse of electricity should operate wash, depending on position of wiper. I stripped down one of these wiper units, and it is a complicated system of gears and worms, operating a keyed lever which operates electrical contcts for the squirt! There is a nice picture of the inside of the unit at: http://www.mindspring.com/~houlihan/merc/hlwiper.htm
from which you get an idea of how it works and Bosch also have a sticker on the outside casing showing a wiring diagram for the motor and plug which is useful, but still has not solved my problem. I do not advise pulling thses apart though - they are very difficult to get back together and the plastic lugs on the casing snap off. Either I have another driver's side duff motor unit, or I have a broken wire in the earth connection from the unit to the car, or there is something wrong with the control stalk. Actually, thinking about it, a broken wire should not be the cause since the passenger side operates momentarily before the fuse blows.
I am still stuck and need help on this one, and getting ever more frustrated by it.

 

[Andy Cottrell]

John,
Have finally found time to measure the circuit resistance:
Removing the plug from drivers side headlamp washer motor, and measuring the socket ( all 4 terminals to earth) gives about 2 ohms. Didn't matter whether the "ignition" was on or off.
Measuring the plug ( with terminal one being the left hand one closest to the rear of the car and the drivers side front wing,terminal 2 being the right hand one closest the rear of the car and passenger front wing, 3 being left hand closest to front bumber, 4 being right hand closest to front bumper)
Pins 1 to 2 are 25 ohms,
Pins 1 to 3 are 25 ohms,
Pins 1 to 4 are open circuit,
Pins 3 and 4 are a short circuit ( I think ) although this was difficult to measure properly without removing the headlight.
Hope this may be of help.

 

[MotardMan]

How was the problem resolved?

 

[davidsl500]

That thread is 14 years old !!

 

[MotardMan]

Yep, and I'm 52!

I hate open ended threads. Also, I've just bought a 124 estate with lazy headlamp washers and was Googling for answers.

Apologies for waking the zombies.