Low Voltage at Wiper Motor

[ScoobyJawa 23]

Hi Guys

 

Finally getting round to looking at my slow wipers (which I've already replaced with wipers from a Saxo and greased the spindles).

 

I took off the scuttle panel and connected up a multimeter to the Red and White wires on the outside of the motor, with the wipers on normal speed I was only reading 3.5-3.7 volts.  I should be seeing 12v ish no?

 

Just wondering if anyone knows of a fix/workaround for the problem?

 

Thanks

Neil

[Richard309Sri XU5JA 205GTi 8]

I have a 309 but I think the wiper motor is the same if not very similar. 

 

mine got water in it and wouldn't even move. Just got hot when turned out. I ended up having to take the whole thing apart. Then clean off everything including the little three brushes. I remember the motor is really smaller than I would expect. The gears I know help but still seemed little pitiful even LoL I then reassembled with new grease in the gears and new seal to stop water getting into it. now it's brilliant fast and stronger.

 

Was there any damp or little bit of rust loose inside yours? It says you greased the spindles already 

 

Yeah that sounds low. I can't remember exactly what voltage I measured. Yeah I think I was testing on the work bench with 12v because I thought it was that supplied. 

 

I know I started looking into the relay because I thought it was the wiring. You can get a replacement relay fairly cheap - on mine it was a blue one. 

 

Now I remember though there are two voltages I think for the different speeds.

Do you get a higher voltage for the fast wipe speed? 

 

I would go and measure the voltages again but I put the scuttle panel back and can't get to the connection easily. Unless there is a smart way to check from the fuse board itself. 

 

 

Edited September 20, 2021 by Richard309Sri XU5JA 205GTi
mistake in reading the post

[DamirGTI 342]

As above , opening up and cleaning the motor and greasing the gear mechanism makes wonders ... brushes are usually still good , often no need to replace , but the commutator surface tends to get covered in dirty/blackened layer , fine grt. sanding paper or red (coarse) and gray (fine) scotchbrite pads and clean that up it'll the nice fresh copper layer .

 

Check motor earth too , it's earthed near the motor fastened onto the scuttle panel and often oxidizes/rusts like mad as it's opened to environment ... disassemble and clean up , and peel off some of the wire insulation from the ring terminal side inspect if the wire/copper strands are rotten/blackened underneath (common for most of the engine bay wiring) , if so will need to cut and replace with fresh bit of wire or at least clean up and fit/solder new ring terminal . When done , paint over earthing point or apply some vaseline to protect the connection from the water/moisture ingress  .

 

 

D

 

 

Edited September 20, 2021 by DamirGTI

[ScoobyJawa 23]

Thanks for the reply's guys.  I've retested the voltage at the motor with the engine on and in normal and fast modes.  Normal is seeing about 3-4 volts on the motor terminals, and high is even worse showing it bouncing between 0 and 2 volts!!!! So theres defo a problem in the feed to it.

 

I've taken the motor off and will clean it up, will sort a new relay and see how it goes....

 

I've tried to trace the earth, but the 5 pin connector block that plugs into the wiper motor has a grey lead for earth, and the wiring is then all wrapped together and are passed through the bulkhead into the engine bay and disappears behind the coolant reservoir.....  

 

 

Edited September 21, 2021 by ScoobyJawa

[welshpug 1,657]

never heard anyone teat across the pins like that before, you test the incoming with the plug disconnected.

 

i doubt the motor would even move with a true 3v to it.

[DamirGTI 342]

Ditto ! 3v is way too low for even make it turn ..

 

Try to feed direct 12V from the battery with an jumper wire (add fuse) to the motor with original earth , and see what happens .. then try original power supply but make separate/another jumper wire to earth (earth on battery neg.) .

 

Not sure if there was difference on earthing point during the years of production ?! anyhow on a Ph1 car , it's near the motor on/under the scuttle panel .

 

D

 

 

[ScoobyJawa 23]

To be fair with the wipers on the screen they do barely move! Seriously slow and last time they just stopped mid wipe and then eventually went again.

 

Mines a phase 2 1990 so it looks like they’ve moved it.

 

I was thinking of doing exactly that with jumper wires once I’ve cleaned up the motor so will have a play.

[Richard309Sri XU5JA 205GTi 8]

On 9/21/2021 at 4:36 PM, welshpug said:

never heard anyone teat across the pins like that before, you test the incoming with the plug disconnected

yeah I was testing mine with the connector unplugged. 

if testing with it plugged in the voltage will be much lower as some of the voltage will be "used" by the motor. 

(can remember the right way to describe it) 

 

maybe the haynes wiring diagrams show where it/the wires and the relay are connected to the fuse board. then test those terminals on the fuse-board? - for testing the supply in, in another way  

 

 

[Richard309Sri XU5JA 205GTi 8]

ok so the haynes 205 1983 -1995  0932 manual shows the wiring going to terminal mainly "A" and "S" 

 

strangely got the wiper relay twice "98" x 2 = that's got to be an error. 

 

could be possible to test the voltages on the fuseboard - 

 

I might have a go after lunch and see what readings I get - on and off - if those are the right blocks to test

 

might be tricky to test the relay whilst plugged in? 

 

I guess if it clicks on and off which is clearly audible then it's working - it couldn't give a low voltage - 

it will either be working or not. there could only be a fault in the wiring from the fuseboard to the motor where the 

voltage could drop or the earth is bad yes. 

 

on this 309 the rear wiper won't work unless the boot is shut at the latch is also the earth return, realise the earth is important to complete the circuit 

 

[ScoobyJawa 23]

Fixed - I'm well chuffed.  Thanks for all the replys.

 

Got the motor off and cleaned that all up as per Matts guide (though it wasn't really that bad at all), while looking I checked the spindles again.  I could barely turn them by hand.  So its taken a day of soaking them in penetrating oil and a LOT of brute force pulling the plastic off, but I eventually got there.  They were so rusted up I'm surprised the motor even had the ooomph to move them.  Used a dremel to clean up all the rust, cleaned out the plastic with wd40 and a rag, greased them all up and put them back together, its now perfect   

[DamirGTI 342]

Nice one !

 

Yeah it's really bad design of the wiper mechanism , recommended periodical inspection cleanup and greasing , shame really 106/saxo mechanism is much better designed but cannot be retrofired on a 205 .

 

D