New replaced rear windscreen motor only works in reverse gear and rear washer jet’s not at all

[Nexus21]

Hello to you all and I hope you are well.

 

Today I fitted the brand new rear wiper motor which only works when I put the car into reverse, after me stripping down and greasing up the old motor and getting zero.

 

Ive since re-fitted the old motor today just to test and that now works! but also only in reverse gear!!

 

Changed drivers side fuse 41 twice for the motor.

Put a fuse in slot 42 for the washer even though it says empty slot in my Skoda manual.

 

Ive also stripped back the interior carpet/cd stack area at the back and the washer pipe is still intact and joined.

 

No noise at all from rear washer motor when I push forward on the right steering wheel stalk.

 

Sprayed electrical contact cleaner in the stalk.

 

Im flummoxed. Don’t really want to blank it off as it’s a Vrs estate 2010 tfsi and I’ve already spent money on a new motor I didn’t need.

 

Changed all fuses today in the engine fuse box.

 

Also tried all ways in adaptions re wipers in Carista App.Also no problem code showing for this.

 

Any ideas please folks?

 

Thank you very much

 

[Guest]

Try disconnecting the battery for 5 minutes, whilst disconnected turn ignition on and activate horn/high beam flash to completely discharge system(s).

 

Turn ignition off, reconnect battery and retest.

[Nexus21]

Hi MicMac.Ok great I will deffo do that.

 

I did take the battery out to recharge twice as some gremlin fans problem I had drained the battery flat.

 

Ive had the rear wiper problem since buying the car 2 months ago.So far it’s been on the drive more than on the road due to a suspension overhaul and coolant sensor wiring issue that’s scared me from blowing the engine.

Will try your suggestion tomorrow but also considering buying a new 096 batteryanyway,you think that would be money well spent?

 

Thanks again.

[Guest]

If the battery has a magic eye that indicates good, it's charged up and turns the engine over in a lively fashion resulting in an immediate start I would defer buying another one whilst it still works.

 

The original fault(s) may have been triggered by a flat battery from lack of use, when the engine is cranked all the power goes to the starter motor.  Not a problem with old analogue cars but today's digital electronics can lose their settings during a brown out where the starter motor draws so much from the battery that there's not enough reserve in it to trickle to the electrickery parts.

 

Fingers crossed a total power loss will reset whatever has gone haywire and with regular use the battery stays good.

[Nexus21]

Well that excellent answer has saved me about £70 for a new battery this morning so I Thank You very much for that.

 

Magic eye is green,no problem starting at all and it reads 12.3v after a good few days no use apart from Carista on/off tests.

 

Will be doing your suggested procedure in the next couple of hours fingers crossed too and I will report back.

 

Have a great day one and all.

[russ17]

If you are interested, I did a strip down and motor brush "tweek" on my estate rear wiper motor, to get it working.

 

 

 

[Nexus21]

Thank you Russ.

I did actually do the same strip down myself before buying a new motor.

 
The old one now works after testing- exactly the same as the new one!

 

On doing some more reading on here tonight on posts going back some years,it seems that the rear wiper ONLY works when in reverse gear on the mk2 Octavia!! Doh!!

 

Anyway it seems the motors are prone to failure so all is not lost,I’ve a spare for if it happens 

 

Thank you everyone for your help.

 

This is the best motoring forum I’ve joined over various marques of car ownership in the past.

[Guest]

@Nexus21

 

The rear wiper on the Mk2 Octavia operates:

 

1. At any time when the right stalk is pushed forwards, screen wash is expelled for as long as the stalk is pushed.  Upon releasing the stalk, the screen wash stops and the wiper continues for several wipes before stopping, it then operates in intermittent single wipe mode, being cancelled by pulling the right stalk backwards.

 

2. If you have auto rain sensing front wipers and they are activate and you select reverse gear, the rear wiper again operates in intermittent single wipe mode.

[Nexus21]

Well then I’m back to square one then MicMac.Only works when I put into reverse gear and also zero sound or screenwash -nothing from the rear washer jet.

 

I have driven this car about 500 miles since buying it mid November.

Broken wiring for sure ecu to coolant temp sensor - tonight resigned to get an auto electrician to do it- I give up.

 

Complete wrong front springs after getting new front struts fitted.

 

it’s been up n down on axle stands more than a whores knickers.

 

I just really want to drive it!!!

[Guest]

@Nexus21

 

Hahaha I feel your pain, on the plus side most electricals are monitored and a good diagnostic tool should pick up DTC if they exist.

 

Don't dive straight in when interpreting DTC, they can point to a consequence not a problem.

[Nexus21]

Ah yes many thanks again.I do have a Carista subscription which shows mainly 2 points I cannot clear

* consistent coolant temp sensor fault P0659

* also consistent Acuator Supply Voltage “A” Circuit High......

 

which could.... be from the coolant sensor problem?

 

ive cut the brown and yellow wires to test but getting 0 volts after 2x genuine new sensors

The rest im not too concerned with -

( Heating/Ac sensors) and drivers heated mirror which clear when reset

 

I attach Carista results if anyone sees anything that jumps out please

 

DETAILED ECU INFO

ECU info obtained with Carista 540099 for iOS:

VIN: TM###############

Engine
Part #: 1Z0907115AF
Component: 2.0l R4/4V TFSI
Software version: [none]
ASAM/ODX identifier: [none]
Coding: 0203000C18070160 (hex)
Fault codes:
P2185 Engine Coolant Temperature Sensor 2 (G83), Circuit High
P3087 Manufacturer-specific code

ABS
Part #: 1K0907379AS
Component: ESP MK60EC1 
Software version: 0105
ASAM/ODX identifier: [none]
Coding: 163B601C092300FC681306E4901C0081340800 (hex)
[No fault codes]

Steering angle
[ECU not present]

Power steering
Part #: 1K0909144J
Component: EPS_ZFLS Kl. 74
Software version: [none]
ASAM/ODX identifier: [none]
Coding: [none]
Fault codes:
03803 Steering Angle Sensor for Steering Aid: No or Incorrect Basic Setting / Adaptation 

Airbags
Part #: 1K0909605T
Component: Q4 AIRBAG VW8
Software version: [none]
ASAM/ODX identifier: [none]
Coding: 20788 (decimal)
[No fault codes]

Headlight aiming
Part #: 5M0907357C
Component: AFS-Steuergeraet
Software version: [none]
ASAM/ODX identifier: [none]
Coding: 1507610 (decimal)
[No fault codes]

Instrument cluster
Part #: 1Z0920903L
Component: KOMBI 
Software version: 0405
ASAM/ODX identifier: EV_Kombi_UDS_VDD_RM09
Coding: 410F01 (hex)
[No fault codes]

Immobilizer
Part #: 5K0953234
Component: IMMO 
Software version: 0405
ASAM/ODX identifier: EV_Immo_UDS_VDD_RM09
Coding: 000000 (hex)
[No fault codes]

Central electronics
Part #: 1K0937087J
Component: BCM PQ35 H 
Software version: 0615
ASAM/ODX identifier: [none]
Coding: 40180AF0A049B1C040100080110091E4422000AE725D8960E30440040040 (hex)
[No fault codes]

Body/convenience system
[ECU not present]

Driver's door
Part #: 1T0959701T
Component: Tuer-SG
Software version: [none]
ASAM/ODX identifier: [none]
Coding: 756 (decimal)
Fault codes:
00943 Heated Exterior Mirror: Driver Side (Z4)

Front passenger's door
Part #: 1T0959702R
Component: Tuer-SG
Software version: [none]
ASAM/ODX identifier: [none]
Coding: 756 (decimal)
[No fault codes]

Rear left door
Part #: 5K0959703A
Component: Tuer-SG
Software version: [none]
ASAM/ODX identifier: [none]
Coding: 144 (decimal)
[No fault codes]

Rear right door
Part #: 5K0959704A
Component: Tuer-SG
Software version: [none]
ASAM/ODX identifier: [none]
Coding: 144 (decimal)
[No fault codes]

Steering wheel
Part #: 1K5953521BJ
Component: LENKS.MODUL 
Software version: 0140
ASAM/ODX identifier: EV_SMLSNGVOLWSXS
Coding: 0080160000 (hex)
[No fault codes]

Heater & air conditioning
Part #: 3T0907044AR
Component: Climatronic 
Software version: 0401
ASAM/ODX identifier: EV_Climatronic
Coding: 0000000002 (hex)
Fault codes:
9471765 Manufacturer-specific code
9472021 Manufacturer-specific code

Radio
Part #: 1Z0035156G
Component: BOLERO 
Software version: 0029
ASAM/ODX identifier: [none]
Coding: 050004000001 (hex)
[No fault codes]

CAN network gateway
Part #: 7N0907530
Component: J533 Gateway
Software version: [none]
ASAM/ODX identifier: [none]
Coding: E9817F0600020200002303 (hex)
[No fault codes]

Obtained with Carista 54###### for iOS.
Download app: https://itunes.apple.com/app/id954363569
Facebook: https://www.facebook.com/caristaapp

 

Thanks so much in advance gentlemen and ladies 

[russ17]

10 hours ago, Nexus21 said:

Well then I’m back to square one then MicMac.Only works when I put into reverse gear and also zero sound or screenwash -nothing from the rear washer jet.

 

I have driven this car about 500 miles since buying it mid November.

Broken wiring for sure ecu to coolant temp sensor - tonight resigned to get an auto electrician to do it- I give up.

 

Complete wrong front springs after getting new front struts fitted.

 

it’s been up n down on axle stands more than a whores knickers.

 

I just really want to drive it!!!

@ Nexus21

 

Are the front wipers operating correctly?

 

To solve this, lets apply some reverse logic. You know that you have power, as the wiper will work under certain circumstances. The CANBUS control is therefore working, but there is something telling the wiper to be "disabled" in all circumstances, except when in reverse.

 

I am aware that the wiper is disabled when the boot is open.

 

What happens to the boot interior light? is it on all the time, or does it go off when the boot is closed?

 

Theory being that if the boot closed switch (or sensor if that is how it is monitored - I haven't checked how it is done) is not operating as expected, then perhaps this explains the lack of wiper operation as the ECU detects that the boot is open, so disables the wiper operation. IT is possible that the boot open detection is achieved by measuring the current drawn by the interior boot lights, but I don't know this for sure.

 

When the wiper operates, does it park itself in the correct position?

 

I see you replaced the wiper motor. There is a metal disc on the drive gear which contacts the fingers on the PCB, which tell the system when the wiper is in the park position.

 

Is it possible that the metal disc is missing or damaged or the fingers are not in contact with the disc? You could measure the resistance between the two contacts circled on the PCB, which should be "short circuit" at all times, except when the motor is in the "park" position (The cut out in the metal disc is the park position, so one finger will loose contact with the disc in the park position),.

 

To test this, you would need to get the motor away from the park position (by operating the wiper when the car is in reverse in your case), then disconnect the wiper motor fuse, to make the wiper stop away from the park position. You will probably need to remove the wiper from the car to access to the PCB after you remove the plastic cover on the motor, once you have moved the motor away from the park position.

 

Good Luck

[davidwhite]

Applying logic as russ17 suggests would imply that both motors have the same fault ? 

 

Do the luggage compartment lights work because since changing my tailgate mine don’t and I’m led to believe the fault is on one of the tailgate lock mechanism micro switches ( haven’t checked yet but on the ‘ to do ‘ list when better weather arrives )

[Nexus21]

Thank you both gentlemen and I hope you are well today.

 

Oh I hadn’t noticed the boot lights(Circuit) not working,this is a new to me car- I’ve currently got a mobile mechanic out in the snow fitting 35mm front lowering springs to match my fitted back ones!

 

I will have a check out when I can today.

 

Yes front wipers work perfectly as they should.

Checked all possible windscreen contortions with Carista App.

 

Just to reiterate I have,since stripping the estates rear wiper motor and greasing up the parts,fitted a brand new one so that’s also not working from the drivers right stalk- nor the washer motor or wash fluid at all.

 

I really appreciate your time and knowledge everyone-again,fantastic forum.

 

I will report back when I’ve done some more research.

[russ17]

@nexus21

 

When you press the right side stalk (Rear wiper) forwards (away from you) do you hear a relay click from under the steering wheel? You should hear this, even if the motor doesn't move. If you don't get this click, then something in the ECU is preventing the relay from energsing, and hence the motor from operating - I don' t what would cause this however i'm not sure that the "boot open" signal would stop the relay click.

 

[Nexus21]

Hello again Russ and I really appreciate your help.

 

No Sir,zero click when pushing the right stalk forward.

 

Funnily enough it was only the early hours of the am when reading various posts on here that I found out there is yet another relay box under the steering wheel(Comfort control I think it’s called)

 

Id better spend a little bit of non car stuff time with the wife and 4 month old today but 1st light in the morning I’ll be out the gap!!

 

Do you by chance know what relay number that will be for when I rip it apart please?

 

Again Thanks so much to you

[russ17]

Dear Nexus21,

 

 

According to the Haynes manual wiring diagram:

Fuse FB52 50A which is in the engine compartment fusebox is the fuse which provides power to the On-Board power supply unit. The on-board power supply unit contains relays and 3 of these relays form part of the wash/wipe system.

FB16 15A feeds the steering column control unit. This unit gives commands to the on-board power supply which controls the rear wiper and washer pump.

FB31 30A feeds the front wiper motor - this is OK as your front wipers are working.

 

Fuses "FC" are in the passenger compartment - remove the side panel from the dashboard on the drivers side with a flat blade screwdriver.

Fuse FC42 15A feeds the rear wiper and washer pump, by relay control, via the on-board power supply unit.

The rear wiper motor has a permanent 12V live feed through FC11 5A which is identified as "Trailer" for some reason. The washer pump can run in both directions (the relays in the on board power supply reverse the power) and depending on the pump direction, will supply fluid to the front or the rear screens.

The same two relays which are within the on-board power supply to control the washer pump and also seem to supply a control signal to the rear wiper motor PCB, so depending an how the relays are switched, will determine if the rear wiper is operational or not.

 

So in short, the relays cannot easily be checked, only the fuses as stated above. 

 

a quote from your previous post:

"Just to reiterate I have,since stripping the estates rear wiper motor and greasing up the parts,fitted a brand new one so that’s also not working from the drivers right stalk- nor the washer motor or wash fluid at all."

 

Do you get washer fluid on the front screen when you pull the right side stalk towards you? If you do, then this means the washer pump is OK, verifies that Fuse FC42 and FB52 are good and could indicate an issue in the on-board power supply unit.

 

Let us know what you find.

[russ17]

Update:

 

You can possibly get to the relays according to this image: https://www.ebay.co.uk/itm/164187916679?var=0

 

I cannot work out which one is which, but you could try swapping similar relays and seeing of the issue moves elsewhere. There are three single pole relays and two changeover relays:

 

Relay A - single pole type - Horn

Relay B - single pole type - Power Switch "X"

Relay C - single pole type - Heated Rear Window

Relay D - Changeover type - Windscreen Washer Relay 1

Relay E - Changeover type - Windscreen Washer Relay 2

 

It could be that Relay D & E are in one package https://www.ebay.co.uk/itm/GENUINE-AUDI-VW-SEAT-SKODA-WIPER-WASHING-RELAY-377-CONTROL-UNIT-4B0955531A/254744692537?epid=1109331791&hash=item3b4ff78739:g:Mr0AAOSwfEVe51SJ

 

 

Have a look at this video 

You could measure the coil resistance of you have an Ohm meter - I would expect around 300 - 3000 ohms - but it is more likely it will be open circuit (infinite resistance with an ohm meter).

[Nexus21]

Wow.That's all I can say for the effort you have gone to help me on this gremlin.

 

When I bought the car mid nov I knew it would need a suspension overhaul, on sticking Carista on it,a still unresolved coolant temperature sensor issue-hence hardly driving it in case I damaged the engine plus the wiper not working was bugging me lastly.

 

So in trying to rectify the coolant temp sensor(Fitting 2x new Genuine ones) but still no dice I changed out every fuse I could find apart from the 2x50amp maxi fuses in the FB box( Engine next to battery)

 

I also bought a new 70amp relay(I have 2 of these in my engine fuse/relay box.

They are both marked as “100” on the top.Juggled and swapped but no change.

 

This non working coolant sensor was also sending the fans crazy and draining my battery.

2 times in succession after a full 35hrs re-charge it drained the battery over night.

 

Ive since cut the yellow and brown sensor connector wires and joined with a new connector and still no joy.

 

So re-fitted all blade and mini blade fuses.Same.

 

I dismantled the FB box without disconnecting all of the black/red feed cables,prised it apart and there was about a tablespoon of water in between the layers of this box,got a hairdryer and blasted the whole lot for 10 mins.

 

Water was also present in the 3inch? Wide black connector that feeds the radiator fans underneath the front body’ of the car.Electrical contact cleaned and hairdryer and the fans have been silent until 2 days ago.

 

Clutching at straws and against all fight in me, I bought a new battery 096 battery,as i didn’t know the age of the original one, by chance I heard the bloody fans again yesterday even tho I’d not driven the car!Removed the neg battery connection.

So tomorrow’s task was going to be strip the FB box completely and hairdry it full on, in sections.

 

 

 

I can see straight away from your Haynes wiring diagram and photos I took of my own fuse layout in the FC fuse box(Drivers side right panel) That I have a correct 15a fuse in FC42.

 

FC11 ( 5a) is blank/no connection on my car tho I do have at least 2 for “trailer” further down in the fuse box.

 

I think I will have to admit defeat and find an Auto Electrician to open up the ECU, after I have peeled the wipers and scuttle off for him and ask him to re-run 2,fresh wires from ecu to coolant temp sensor.At least the car cooling system will work.

 

Cars are fun but time consuming.

Ask the wife 😂

 

I will report back 

You’re a Legnd Thank You.

 

 

 

[russ17]

I have to say that my Haynes manual is for the 1.9TDi OCtavia 2, so the TFsi "may" be different, but the wiper section "should" be identical across all variants.

 

I think FC11 is a typo in the Haynes manual wiring plan, as in the FC layout diagram, FC41 15A is the permanent feed for the Rear Wiper.

 

I would definitely check and/or swap the relays that sit on the Power Supply Unit, which should be under the steering column area, as you said you are not hearing a relay click when the stalk is moved forward to enable the rear wiper. These relays also determine whether you get washer fluid to the front or rear screen, so check the washer operation too. 

You said that the rear wiper works when in reverse gear only - so when you move the stalk forward, do you hear a click and then the click when you pull the stalk toward you? If you enable the rear wiper then engage reverse gear, do you hear a click? Then take the car out of reverse gear (without moving the stalk), do you hear a click?

We have to establish if the stalk and/or steering control module are faulty, as the commands from the stalk pass through the steering control module. The steering control module also has CAN bus inputs, which give another layer of enable/disable (e.g. reverse gear enabled = operate rear wiper and boot open = disable rear wiper). Testing the outputs of the steering wheel control module are not possible with a meter  as they may be digital commands instead of just 12V present/not present.

 

Have a look at this page: https://workshop-manuals.com/skoda/octavia-mk2/vehicle_electrics/electrical_system/wiring/fuse_holder_and_relay_carrier/removing_and_installing_the_relay_carrier_under_the_vehicle_voltage_control_unitj519_vehicles_as_of_my_09/

 

As regards your coolant sensor issue, the Haynes manual doesn't show engine wiring, and I cannot find anything online, but don't give up, you are making progress, and you will feel satisfaction when you finally solve the problem!

 

There are some users, "Wino" is one, who have access to the Skoda online documentation. Perhaps PM him and ask if he can get a wiring plan of the coolant sensor system, and see if that helps.

 

[Nexus21]

Good morning to you Sir I hope you are well.

 

Yes I have a new 15a in slot 41.I put a 15a in slot 42 also just to cover those bases.

 No clicks from the drivers right stalk.

I do really think it a relay issue now.

 If I can again slip outside and start tearing the dash apart that is my next port of call for sure.

 

Wino has already been a fantastic help with regards the pins ecu- coolant temp sensor(Yellow and brown)

I don’t feel confident removing the ecu after reading horror stories on here though I am more than comfortable doing a continuity test on rack of those wires to see if I get 5v on my now cut at  radiator end sensor cable.

 

Gotta go- wife is not impressed -I’ve already had the front wheels off and spacers fitted today!!

chat soon 

thank you very much again 

[Nexus21]

Found Wino’s ecu-coolant temp sensor for anyone in future 

[russ17]

Just doing some testing on my car (1.9Tdi Estate) - the boot must be fully closed for the wiper to operate.

 

Even if the boot is slightly open, the wiper wont wipe, and if the boot is slightly open, the boot lights will be off, so it must be the micro switch on the tailgate catch that determines the closure status of the boot/tailgate and hence the operation of the wiper.

[Nexus21]

Righto.Sounds a lot easier than ripping the dash apart

 

No clicking from stalk tho.........

[russ17]

Also, when the boot is slightly open, the relays under the steering column do not operate and therefore the wiper doesn't move.

 

As your wiper operates when car is in reverse, this discounts the micro switch on the boot as being the cause.

 

So ruling out what is known:

 

Items which are Good:

 

 

Tailgate Micro Switch (indicates boot is closed, so must be good as wiper works when reverse is engaged) The tailgate switch gives a Ground to pin 18a/8 on the convenience control unit, which I assume is communicated through CAN bus to the Steering Column Control unit, which supplies signals to the On-Board Power Control unit, which controls the rear wiper/washer relays.  

FB52 50A in engine fuse box (supplies power which goes through Relay B, FC41 & FC42 so must be good as wiper works when reverse is engaged)

Relay B - single pole type - Power Switch "X" (supplies power to FC41 & FC42, so must be good as wiper works when reverse is engaged)

Fuse FC 41 & 42 (supply power to motor, so must be good as wiper works when reverse is engaged) 

Wiper Motor (works when reverse is engaged)

The only things it can be are (in order of likelihood in my opinion, if I were in your position):

 

Relay D - Changeover type - Windscreen Washer Relay 1

Relay E - Changeover type - Windscreen Washer Relay 2

Wiper Stalk (just the rear wiper/washer function, as the front wiper operation is OK) - you may be able to test this with a multi meter

On Board Power Supply Unit (under steering column)

Steering Column Control Unit

 

Relays are a definite source of trouble, more the contacts than the operation coil.

Edited 31 January, 2021 by russ17
additional info