lights dim briefly when changing gear?

Talk about the 406's electrical system, what wires do what, how to add extra functionality, etc.

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spongmonkey
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lights dim briefly when changing gear?

Post by spongmonkey »

Hi,

I've noticed at night that for the first few miles my headlights dim slightly at the moment I change gear, it's only brief and only a slight dimming. After a few miles it stops doing it? Operating additional items such as rear heated screen, blowers, radio all together make no difference to the issue it doesn't get better or worse.

Also yesterday morning I've noticed a slight "squeek" noise when the car has been started, eeek, eeek, eeek, not the normal screech at the point of starting, but continuous like a heart beat, and not loud enough to hear when in the car.

I'm thinking alternator belt but I know very little about cars so just an educated guess?
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Captain Jack
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Re: lights dim briefly when changing gear?

Post by Captain Jack »

What a coincidence! I've noticed the exact same thing yesterday during the first few miles when the car is still relatively cold. Must be something to do with alternator not supplying enough current so it takes the power from the battery (when RPM is lower - during a gear change). However, I am probably talking bollocks.
2003 - 2008: 1998 Peugeot 406 2.1 TD 110bhp LX Saloon
2008 - 2009: 2004 Honda Accord 2.2 CDTI 136bhp Executive Saloon
2009 - 2013: 2002 Peugeot 406 2.0 HDI 110bhp Executive Saloon
2013 - 2021: 2007 Peugeot 407 2.2 HDI 170bhp Executive Saloon (mapped to 213bhp :twisted:)
2021 - ????: 2016 Ford Mondeo 2.0 TDCi 180bhp Titanium
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steve_earwig
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Re: lights dim briefly when changing gear?

Post by steve_earwig »

This probably ties-in with the flickering headlamp thread from a few days back.
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steve_earwig
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Re: lights dim briefly when changing gear?

Post by steve_earwig »

spongmonkey wrote:Also yesterday morning I've noticed a slight "squeek" noise when the car has been started, eeek, eeek, eeek, not the normal screech at the point of starting, but continuous like a heart beat, and not loud enough to hear when in the car.

I'm thinking alternator belt but I know very little about cars so just an educated guess?
Eeek! I didn't see that the first time :oops: Does it tie-in with engine speed? What happens if you turn everything (wipers, main beam, heated rear window...) on? Have a good look at your aux (alternator) belt, if you've got any doubts about it's condition renew it - there has been quite a few occasions where a failing aux belt on an HDi has taken out the cam belt (with bank account-emptying consequences) I'm not sure about the eek eek eek heartbeat stuff but you should also watch it running to see if there's anything wobbling about.
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spongmonkey
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Re: lights dim briefly when changing gear?

Post by spongmonkey »

Cheers guys will get my mate to check the belt over and let you know the results
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