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Lights dim with VSC

7K views 16 replies 13 participants last post by  JuneBug 
#1 ·
Has anyone else noticed that the headlights dim when the VSC kicks in but as soon as the light goes out, they are back up to brightness. I was playing around on a quiet road in the snow tonight and noticed a dimming of the lights when the VSC light comes on when I give it a bootful. Is it using that much brainpower that it takes juice away from the lights? FWIW I have an 06 V6 4WD Sport.

I have to say, I am quite impressed with how it works...doesn't take over totally as you can still slide it a small amount and drive it rally-style. I have the over-ride instructions in the car in case I get stuck and need to turn it off.

Just wondered if anyone else had noticed the lights dim
 
#2 ·
mcvitie70 said:
Has anyone else noticed that the headlights dim when the VSC kicks in but as soon as the light goes out, they are back up to brightness.
I have not noticed that myself but it would make sense that it happens.

Part of the VSC system reduces the engine power to stop wheelspin. When the engine RPM's drop, so does the alternator output. With all your accessories on like headlights, rear window defroster, seat heaters, blowers, wipers , etc, etc, the drop in alternator output would be even more noticible.

Just my theory, but I'm almost certain the VSC processor is not using any more current that it does when it is just monitoring the sensors.

Rick
 
#3 ·
If you read the description of VSC in the manual, it mentions that it provides "integrated control" of the following:
- ABS
- brake assist
- traction control
- engine control
- electric power steering
- AWD system

Although I haven't noticed the lights dimming when the stability or traction control system kicks in, I can see how several of these functions being activated at the same time could put a higher load on the electrical system.

Does your RAV4 have the towing package with heavy-duty alternator?
 
#4 ·
bmorton said:
If you read the description of VSC in the manual, it mentions that it provides "integrated control" of the following:
- ABS
- brake assist
- traction control
- engine control
- electric power steering
- AWD system

Although I haven't noticed the lights dimming when the stability or traction control system kicks in, I can see how several of these functions being activated at the same time could put a higher load on the electrical system.

Does your RAV4 have the towing package with heavy-duty alternator?
Good points made. Say, does anyone know the added amps that optional Tow Package alt makes over the std version? I've got that optional alt. and am curious.
 
#8 ·
anytime the ABS kicks in the lights dim, and since the VSC uses the abs system to brake wheels to get back stability, that's normal.
 
#10 ·
Yes! I've noticed that just tonight! I was making a turn into my parking lot and I thought I'd brake hard for the ABS to kick in and then turn at the same time to see if the VSC will help me turn in. All the while, this was on about 1/2" of slushy road. The ABS started grinding the disc brakes and I immediately noticed my headlights dim (it was 9pm). Then the lights lit brighter to normal. Interesting...
 
#11 ·
I had the same problem in our first winter storm, 4WD and VSC were kicking in and out and the headlights would dim. When I went into the dealer I asked them about it and they confirmed it was the VSC and 4WD systems causing the dimming and wrote on my paperwork that the tires that come on the vehicle are not intended for winter driving! I run winter tires anyway, I just hadn't put them on at that time. Now that the winter tires are on I haven't noticed the lights dimming, more than likely due to the fact that the VSC and 4WD systems don't have to work as hard with the added traction of the X-Ice tires.

Still laugh at what they wrote. It's hard to believe they would sell a 4WD that the sales people harped about winter driving capabilities but the tires are not intended for it :roll:
 
#13 ·
I just found it funny how the sales department said it was such a great vehicle in the snow with all season tires, then the service department tells you the tires aren't meant for the snow.

I've run winters on every vehicle I've owned so I knew different. Goes to show, they'll say anything for a sale.
 
#15 ·
Yes it must be the ABS since the 4WD only draws 3 amps max.
 
#17 ·
Carbon, mcvitie70 made that post 4 years ago. Let's hope he's not still on the original battery!
 
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