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2008 stelvio headlight

Chadlebowski

Cruisin' Guzzisti
Joined
Jul 28, 2015
Messages
149
Location
West Sussex; UK
I'm struggling with the electrics on my 2008 stelvio.
No license plate light, no horn, no access to glove-compartment. Can flash full beams with ignition in standby, but fullbeam on showing on dash when engine started (and fullbeam switch does nothing).
I've checked fuses and relays, nothing seems to fix it.
Any tips?
 
Sounds like a cut wire or short ?
Anything happen just before things stopped working ?

I know everything is hiding in a wiring harness, but can you trace/follow the wires from the tail light back to where they connect to something ?
Check each wire with a ohm meter for continuity and no short to ground ?
 
Sounds like a cut wire or short ?
I was afraid of that...

I replaced the licence plate light fitting, the bulb lit up but then immediately went out on engine start.
Also changed the left headlight connection. I noticed the RH headlight has three wires, whereas the left only has two.
 
I replaced the licence plate light fitting, the bulb lit up but then immediately went out on engine start.
Also changed the left headlight connection. I noticed the RH headlight has three wires, whereas the left only has two.

Since the light came on then went off at start this is beginning to sound like a logic issue. Study the schematic in the downloads to see what is going on (look closely at the ignition switch). The right side has bot high and low beam so three wires. The left is only high so just two.
 
I'm struggling with the electrics on my 2008 stelvio.
No license plate light, no horn, no access to glove-compartment. Can flash full beams with ignition in standby, but fullbeam on showing on dash when engine started (and fullbeam switch does nothing).
I've checked fuses and relays, nothing seems to fix it.
Any tips?

——————

I was afraid of that...

I replaced the licence plate light fitting, the bulb lit up but then immediately went out on engine start.
Also changed the left headlight connection. I noticed the RH headlight has three wires, whereas the left only has two.

Posts like this are literally maddening.

Descriptions like this simply are impossible to understand. Correct, precise communication is a basic requirement to help solve your issue.

I cannot tell if you experienced a:

1. Sudden and unexplained failure.

Or

2. You modified something (I still am unsure) and then your troubles began.

Can you please clarify this?
 
Posts like this are literally maddening.

2. You modified something (I still am unsure) and then your troubles began.

Can you please clarify this?

I would say recent change

I was afraid of that...

I replaced the licence plate light fitting, the bulb lit up but then immediately went out on engine start.
Also changed the left headlight connection. I noticed the RH headlight has three wires, whereas the left only has two.
 
I would say recent change

Thanks but this doesn't help one bit.

The problem lies in the inaccurate, incomplete, and out of sync, timeline.

I'm struggling with the electrics on my 2008 stelvio.
No license plate light, no horn, no access to glove-compartment. Can flash full beams with ignition in standby, but fullbeam on showing on dash when engine started (and fullbeam switch does nothing).
I've checked fuses and relays, nothing seems to fix it.
Any tips?

I have no idea what "Can flash full beams with ignition in standby, but fullbeam on showing on dash when engine started (and fullbeam switch does nothing)." means.

What do you specifically mean by "I've checked fuses and relays, nothing seems to fix it."?

Checked fuses and relays how? You've swapped out the relays for known good ones?

FWIW: Headlight issues in the Stelvio are virtually always fused relays and this is very well documented on numerous posts here on the forum.

I've personally fixed several with fused relays exhibiting headlight functionality issues.

I was afraid of that...

I replaced the licence plate light fitting, the bulb lit up but then immediately went out on engine start.
Also changed the left headlight connection. I noticed the RH headlight has three wires, whereas the left only has two.

Why did you have to replace the light fitting? How did you do this? When in this timeline, did you do this?

Why did you change the left headlight connection? What do you mean by this? Did you cut the wiring loom and splice in a new connector, and if so, why?

A much more accurate and helpful timeline of events would help to sort our your issues.

For example:

"Bike was running perfect" or "I just acquired the bike and this is what worked and what did not", or "bike was in an accident, necessitating the replacement of the following in order to get things to work". Be specific please.

I then changed the ________ which then precipitated the ____ not working. So I then did ________ which resulted in ________. So I changed _____ and then ____ happened.

I have checked fuses and relays by doing the following ________ and the results of this were ______.


I suggest this methodology because if you moved from working to non-working, then there is a proximate cause of the "no longer working" condition. The trick here is to be accurate in both the timeline and the events that have taken place.

This is the pathway taken by every professional mechanic in trying to ascertain what was, what changed, and what happened.

An accurate, sequential timeline of events will aid in the isolation of your issue.

Wires do not suddenly "pinch", nor do circuits normally suddenly stop functioning. There are reasons and causes - Cause and Effect as it were.

If you can clean up your information, then I'm sure I can help you figure it out.
 
Last edited:
Bike was running but failed MOT (Ministry of Transport roadworthiness test) due to license plate light not illuminating, and also due to left headlight casting light at incorrect angle for UK regulations (it was a higher rated bulb).

I cut the stock headlight connector (as it had started to melt) and fitted a replacement using posi-locks. I had previously done this with the RH headlight and have had no problems since.

I initially changed the bulb in the license plate, which still did not work, so I replaced the entire unit with a second hand one (from the molex connector to the bulb). This then precipitated the licence plate light lighting at first, but going out once the engine was started.

The blue full-beam light is showing on the dash, but the left headlight is not illuminated. The horn does not work, nor the glove compartment release. I have switched all three relays for new, with the same result, as well as replacing every fuse. The results have been the same.
 
Since the light came on then went off at start this is beginning to sound like a logic issue. Study the schematic in the downloads to see what is going on (look closely at the ignition switch). The right side has bot high and low beam so three wires. The left is only high so just two.

So the white wire on the left headlight is not spliced in?
Having looked at the wiring diagram, am I right in thinking the only way the horn and headlight would be out simultaneously is with a problem in the LH switch?
 
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