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Blod 1

New Member

• Nov 3, 2020

• #1

hi disco any idea where to look wipers come on with heater fan

 

Interceptorxj

Well-Known Member

• Nov 3, 2020

• #2

No

 

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PaulJM

Active Member

• Nov 3, 2020

• #3

Do wipers work correctly ie intermittent , speed 1, speed 2, and self park with the heater fan turned OFF. With heater fan on are they running continuously speed1 ? What model disco and year

 

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Blod 1

New Member

• Nov 3, 2020

• #4

The wipers work fine they just come on with the heater fan and will not stop till I switch off the fan
They work fine apart from that you can change wiper speeds as well with the fan running
The disco is 1997 diesel

 

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PaulJM

Active Member

• Nov 3, 2020

• #5

I've had a look at circuit diagrams and can find no common connections between both circuits. They both derive some power from adjacent fuses on facia fusebox behind flap on drivers side. And there is also a connection from the wiper relay to the BCU which is also in close proximity. The only thing I can guess at is there may be water ingress around that area that is triggering BCU to turn wipers on when heater fan is powered on.

 

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Blod 1

New Member

• Nov 3, 2020

• #6

PaulJM said:

I've had a look at circuit diagrams and can find no common connections between both circuits. They both derive some power from adjacent fuses on facia fusebox behind flap on drivers side. And there is also a connection from the wiper relay to the BCU which is also in close proximity. The only thing I can guess at is there may be water ingress around that area that is triggering BCU to turn wipers on when heater fan is powered on.

Click to expand...

 

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Blod 1

New Member

• Nov 3, 2020

• #7

Thank you a place to start it has been raining heavily for a few days so could be it

 

sierrafery

Well-Known Member

• Nov 3, 2020

• #8

PaulJM said:

I've had a look at circuit diagrams and can find no common connections between both circuits. They both derive some power from adjacent fuses on facia fusebox behind flap on drivers side. And there is also a connection from the wiper relay to the BCU which is also in close proximity. The only thing I can guess at is there may be water ingress around that area that is triggering BCU to turn wipers on when heater fan is powered on.

Click to expand...

Dont spend time with D2 diagrams mate cos it's about a '97 D1 here which doesnt have BCU

 

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PaulJM

Active Member

• Nov 3, 2020

• #9

Was looking at D1 diags, meant MFU sorry for any confusion

 

Shippers

Well-Known Member

• Nov 4, 2020

• #10

Sounds like a classic Landy earth problem...