Switching ON headlights shuts OFF the engine

aargee · 10th March 2010, 16:18

Update - Did a 27.2 Kms drive today & did experimenting on headlights
Result - Nothing happened

aargee · 13th March 2010, 21:02

Another 150+ odd KMS done & not a single problem yet; The MASS guys suggested not to touch anything until the problem crops up again - I agreed with them

Roshun · 19th July 2013, 14:00

Strangely, I've just experienced this very same problem with my Scorpio, which is now 7.5 years old and has done 1.48 lakh Km. I've got Philips 90/100 lights, which have been doing duty for over 5 years (with a couple of bulb replacements). It has a hella wiring kit with relays and ceramic holders.

Now sometimes when I flash the high beam, the tacho & speedo drop, there's a jerk in the engine and the music system goes off and comes back on. Same thing happens if I switch the headlamps on. No issue in parking lamp position or fog lamp position.

I also noticed another problem. At idle, when I had my foot on the brake, the brake lamp, interior lights were flickering (car was at idle just before parking), but revving the engine made them stable. If I switched off the engine and just kept the key in the ignition on position, all lights functioned normally.

Question: Could this be an alternator rectifier issue or a faulty headlamp relay that's earthing?

(Sorry for raking up an old thread - but this problem is more or less identical to aargee's)

itsashishsharma · 21st July 2013, 14:02

Something similar happened with my father's Baleno. Car was in excellent running condition, as good as new at around 20-25K on odo.
Problem was that at idle, the revs would go down till around 400-500 and wouldn't even settle there, on the other hand, while driving, revs will fall down sharply and eventually result in engine switching to off. Even the MASS guy couldn't apprehend the issue. For months it was like this only for us until some random mechanic finding the issue with wiring being bitten by rodents.

being a Baleno, new wiring was either unavailable/costly as hell, so duct tape was used to fix the issue and now for last 6 years or so, absolutely no issues at all !!

RM2488 · 21st July 2013, 20:57

Quote:

Originally Posted by Roshun

Strangely, I've just experienced this very same problem with my Scorpio, which is now 7.5 years old and has done 1.48 lakh Km. I've got Philips 90/100 lights, which have been doing duty for over 5 years (with a couple of bulb replacements). It has a hella wiring kit with relays and ceramic holders.

Now sometimes when I flash the high beam, the tacho & speedo drop, there's a jerk in the engine and the music system goes off and comes back on. Same thing happens if I switch the headlamps on. No issue in parking lamp position or fog lamp position.

I also noticed another problem. At idle, when I had my foot on the brake, the brake lamp, interior lights were flickering (car was at idle just before parking), but revving the engine made them stable. If I switched off the engine and just kept the key in the ignition on position, all lights functioned normally.

Question: Could this be an alternator rectifier issue or a faulty headlamp relay that's earthing?

(Sorry for raking up an old thread - but this problem is more or less identical to aargee's)

It appears to be a weak battery. Here's a simple way to test (when the car has been left alone overnight, ie it is cold):
1. Switch on the interior light.

2. Hit the brakes. If the interior light dims significantly, the battery isn't charged enough. There could be myriad reasons for that.

3. You have mentioned the lights are not flickering without the engine running. But are they dimmer without the engine running? Does cranking and revving make them significantly brighter?

4. If you have a multimeter, check the battery voltage before cranking, and then with the engine idling. Post the readings.

5. Repeat 1-4 after a 30-min drive without headlights.

Roshun · 21st July 2013, 23:09

I have a multimeter and I checked the voltage after a full-night's rest before starting. Standing battery voltage - 12.9 volts. Started the car and it jumped to 14.1 volt for a few minutes before settling at 13.8 volts. The battery is in decent condition - it's 3.5 years old, a Tata Green 80AH battery.

I found a faulty relay that was going crazy (clicking on and off really fast, when this issue happened) - the condensor fan relay (30A). I swapped it with a spare that I had. The problem hasn't recurred so far, so I'm assuming it was the bad relay that was messing up all the rest of the electronics. But I'll observe it for a couple of days and see.

10th March 2010, 16:18	#31
aargee Senior - BHPian Join Date: Jan 2010 Location: TSTN Posts: 6,355 Thanked: 10,060 Times	Update - Did a 27.2 Kms drive today & did experimenting on headlights Result - Nothing happened
	() Thanks

13th March 2010, 21:02	#32
aargee Senior - BHPian Join Date: Jan 2010 Location: TSTN Posts: 6,355 Thanked: 10,060 Times	Another 150+ odd KMS done & not a single problem yet; The MASS guys suggested not to touch anything until the problem crops up again - I agreed with them
	() Thanks

19th July 2013, 14:00	#33
Roshun BHPian Join Date: Oct 2005 Location: Delhi Posts: 151 Thanked: 41 Times	Re: Switching ON headlights shuts OFF the engine Strangely, I've just experienced this very same problem with my Scorpio, which is now 7.5 years old and has done 1.48 lakh Km. I've got Philips 90/100 lights, which have been doing duty for over 5 years (with a couple of bulb replacements). It has a hella wiring kit with relays and ceramic holders. Now sometimes when I flash the high beam, the tacho & speedo drop, there's a jerk in the engine and the music system goes off and comes back on. Same thing happens if I switch the headlamps on. No issue in parking lamp position or fog lamp position. I also noticed another problem. At idle, when I had my foot on the brake, the brake lamp, interior lights were flickering (car was at idle just before parking), but revving the engine made them stable. If I switched off the engine and just kept the key in the ignition on position, all lights functioned normally. Question: Could this be an alternator rectifier issue or a faulty headlamp relay that's earthing? (Sorry for raking up an old thread - but this problem is more or less identical to aargee's)
	() Thanks

21st July 2013, 14:02	#34
itsashishsharma BHPian Join Date: Sep 2012 Location: Bangalore Posts: 889 Thanked: 983 Times	Re: Switching ON headlights shuts OFF the engine Something similar happened with my father's Baleno. Car was in excellent running condition, as good as new at around 20-25K on odo. Problem was that at idle, the revs would go down till around 400-500 and wouldn't even settle there, on the other hand, while driving, revs will fall down sharply and eventually result in engine switching to off. Even the MASS guy couldn't apprehend the issue. For months it was like this only for us until some random mechanic finding the issue with wiring being bitten by rodents. being a Baleno, new wiring was either unavailable/costly as hell, so duct tape was used to fix the issue and now for last 6 years or so, absolutely no issues at all !!
	() Thanks

21st July 2013, 23:09	#36
Roshun BHPian Join Date: Oct 2005 Location: Delhi Posts: 151 Thanked: 41 Times	Re: Switching ON headlights shuts OFF the engine I have a multimeter and I checked the voltage after a full-night's rest before starting. Standing battery voltage - 12.9 volts. Started the car and it jumped to 14.1 volt for a few minutes before settling at 13.8 volts. The battery is in decent condition - it's 3.5 years old, a Tata Green 80AH battery. I found a faulty relay that was going crazy (clicking on and off really fast, when this issue happened) - the condensor fan relay (30A). I swapped it with a spare that I had. The problem hasn't recurred so far, so I'm assuming it was the bad relay that was messing up all the rest of the electronics. But I'll observe it for a couple of days and see.
	() Thanks