Does anyone have an idea why this fuse keeps blowing on my Mk3 vito

[StevoAmigo1]

Hi guys, had this problem for a while now, everytime I put a new fuse in it sparks and blows instantly, knocking out the heater control panel inside the van, and in turn making the rad fan stay on constantly, I noticed this problem not long after my auxiliary belt shredded all around The pulleys, then after my steering angle sensor and steering control module went faulty making the traction control light stay on, (I've since brought a brand new unit from mercedes that i'm waiting to fit hoping the electrical fault doesn't blow the new unit!??) then the power window switch went dead, so far these are the things I've done to try resolve it,

Used xentry diagnostics,

detected aircon fault, and steering column fault, also power window switch.

I've tried disconnecting the whole steering column unit and putting a new fuse in which blown, tried disconnecting the heater control panel connector, again fuse blown, also disconnected the rad fan and aircon power, every fuse blown, I've searched for bear wires shorting anywhere and cannot see any. Checked connectors Inside van for any green gunk, and all clean. I'm at my wits end with this van now, right now I use it for work I have no horn or drivers airbag working with traction light on, but I'm worried if I fit this new steering control module this electrical fault is going to blow the new unit, so £380 down the drain. Can anyone shine any light on this thanks?

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[StevoAmigo1]

Bump, any one got any suggestions?

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[M80]

I'm assuming the Mk3 is the 447?

 

[StevoAmigo1]

I'm assuming the Mk3 is the 447?

Yes mate it is

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[curious]

When Xentry diagnoses a fault it will often guide you through a series of tests that may help with further diagnosis. Some of thses tests you may be able to do with Xentry. Others, you nay need to use a multimeter, for example.

 

[StevoAmigo1]

When Xentry diagnoses a fault it will often guide you through a series of tests that may help with further diagnosis. Some of thses tests you may be able to do with Xentry. Others, you nay need to use a multimeter, for example.

If its a short circuit, would Xentry detect this as. Fault? And I've no idea where to start with a multimeter. Seems the problem is on the heating side of electrics anyway

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[M80]

I've only played on the 639's.
On the 639 I can't see a separate fuse for the dash heater.
Could this fuse power that and it's faulty. Star should have picked that up though.

If I remember correctly the dash heater is powered below 8C. I can certainly feel the warm air at the vents when I start up, and before the coolant could be heating them, can you?
Will this fuse still blow when the coolant is up to temp, and the heater 'shouldn't' be called for?

 

[curious]

If its a short circuit, would Xentry detect this as. Fault? And I've no idea where to start with a multimeter. Seems the problem is on the heating side of electrics anyway

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It may hopefully guide you with further tests to eliminate/confirm where the problem may be.

Your Xentry indicates it could be an aircon, steering column, power window problem. Very unlikely to be all three but further tests to narrow it down.

 

[StevoAmigo1]

I've only played on the 639's.
On the 639 I can't see a separate fuse for the dash heater.
Could this fuse power that and it's faulty. Star should have picked that up though.

If I remember correctly the dash heater is powered below 8C. I can certainly feel the warm air at the vents when I start up, and before the coolant could be heating them, can you?
Will this fuse still blow when the coolant is up to temp, and the heater 'shouldn't' be called for?

Yes mate it still blows the fuses even when upto temp, even though the heater control panel is off due to the blown fuse, I still feel a bit of heat coming out of the vents when driven around

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[StevoAmigo1]

It may hopefully guide you with further tests to eliminate/confirm where the problem may be.

Your Xentry indicates it could be an aircon, steering column, power window problem. Very unlikely to be all three but further tests to narrow it down.

I've sorted the power window now I replaced the switch so that all works, but just worried if I fit the new steering column it will blow it, because of the electrical fault.

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