HELP! Check engine light is not visible...failing CA smog check.

redscare

Well-known member
Joined
Jan 20, 2009
Location
Boulder Creek, CA
TDI
2014 Sportwagen TDI
Hi, This forum has been as immense help. Now I need a little more.
My problem is my check engine light works, it is just not visible during the day.
It is barely visible at night. I understand the instrument cluster is made up of LEDs.
So, do I pull the cluster and replace it, or will it perpetuate with a new cluster?
Could this be caused by a short in the harness?
Now in the fine state of California, if you fail a smog check, the state(at their discretion) can reimburse up to $500 to fix a vehicle to pass smog. I have to check if I still qualify for reimbursement.
Does anyone know a smog station who might be willing to state the light is visible(just needs to be very dark)?
Other than the light, the car runs perfectly, no codes or issues.
Car is a 99.5 Golf gls. has 200K on her now.
Thanks for any input. Need to get this taken of before the end of the month.
 
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Nutsnbolts

Vendor , w/Business number
Joined
Nov 1, 2001
Location
Weare, NH
TDI
2000 Jetta, Silver Arrow
Unfortunately, the light is controlled by the clutser alone, not the harness. If you can get to the board and check the V going to the LED, then you can determine if the LED is gone, or its driver. Otherwise, the only option would be a new cluster, but the installer must have VAG-TACHO to get the SKC from the old cluster. New clusters are still available online...

-Rich
 
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jcrews

Top Post Dawg
Joined
Jul 28, 2007
Location
Round Rock, TX - VCDS
TDI
All gone
The light is controlled by the ECM. It normally keeps the light off by pulling the cluster pin low. When the lamp is on, the path to ground is opened, and the lamp turns on as it finds a path to ground within the cluster.

You can check the lamp by removing the pin from the blue connector, pin 32, on the cluster wiring connector, and reattaching the connector. If the lamp turns on with full power, there is probably a leak to ground in the wiring. I hope you don't find coolant migration. If the lamp is still dim, the LED needs to be tested. It would either be the LED or its power supply/driver.
 

redscare

Well-known member
Joined
Jan 20, 2009
Location
Boulder Creek, CA
TDI
2014 Sportwagen TDI
Hi, thanks for the suggestions. I found a write up to remove cluster, so guess I'll give it try this week. :eek:

I have checked for coolant migration. Didn't find anything, and did the mod just in case.
Thanks.
 
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