Headlight / dash clock light issue

[Matt1386]

IGood evening all. 

I have recently purchased a 1.6 2007 Berlingo as a run around for work.

On the last couple of weeks I’ve started having an issue when I have the headlights on.

The headlights, aswell as the dash clock lights will all of a sudden go out then come back on straight away. Sometimes this happens just the once, other times it can happen 3 or 4 times in a row straight after each other

It’s not usually straight away, I can be driving for 30 minutes or an hour before it starts happening.

Any ideas on starting points for me to check please ? 

Thanks very much for any help

Matt

[Gryffindor]

I would start by checking all connections including fuses, bulbs, wiring connectors, and breaks or wear & tear in cables, trapped cables, and so on.

The loss of supply could be due to a break in the circuit (a connector unplugged but touching except when it gets shaken, or a wire broken but ditto) or due to high resistance in the circuit (dirty fuse blades, bulb prongs, frayed wire cables contacting other objects, etc.)

Or it could be an earthing issue, where the lighting supply is getting momentarily earthed by something (again, such as a damaged wire touching the bodywork for example).

Does it happen when you go over bumps or brake or accelerate? Does it happen when you're parked with the engine off (i.e. when there is no mechanical or physical disturbance to the car at all)? Might be worth trying this for as long as it would take to happen on the road. If it is triggered by physical disturbance, it is probably a dodgy connection as above. If not, it may be something else - a communications or signals issue?

[Gryffindor]

PS have you tried tapping and wiggling the headlight switch stalk?

[Matt1386]

Hi Rasputin. Thanks very much for your replies.

I haven’t tried wiggling or tapping the headlight stalk so I will try that first.

Regarding when it happens, it’s anytime really, bumps or any sort of disturbance from the road don’t make it happen.

The last couple of times it has happened I’ve actually been driving on the motorway, steady away for maybe a good couple of hours sometimes, then all of a sudden it just decides to flicker on and off repeatedly a few times, the dash / clock lights go out aswell as the headlights.

Thanks again for your help

Matt

[Tomcat3]

Check battery terminals are nice and tight also.

[Matt1386]

Thanks Tomcat. Will check this also and report back tomorrow

[Gryffindor]

How d'you get on? The truly intermittent nature does seem to suggest a damaged/compromised/worn electrical connection, making contact most of the time but not always? Both headlights and dials being affected is what made me think of the headlight switch stalk - it turns both on and off together too. Could be dodgy contacts in its connecting plug, or in the switch's innards, or somewhere else in the wiring which feeds to or leads from it?