Lambda Light

[SoCalDMC12]

Howdy Folks... question about the Lambda idiot light...

A few months ago I had my car smog inspected (CA state requirement), and it passed with flying colors. Shortly after, my car turned 50k miles, and the Lambda light came on.

My understanding is that the Lambda device is simply a counter that sets of a warning to have your emissions system inspected at X miles. If this is the case, can I just reset the Lambda counter? Is this a difficult procedure?

Thanks!

- Geoff

[sdg3205]

You need a special tool. Or you can remove it and do it manually. Or just unplug it!

[DMCVegas]

The LAMBDA light is designed to come on every 30,000 miles. The reason is because since it's a single-wire O2 sensor without an internal heater, it doesn't last as long as modern ones. So when the light comes on, it's time to replace your O2 sensor.

Above your pedal box is the LAMBDA counter it goes from 0-999, but will light up as soon as it hits 100. It is supposed to be representative of how much of the Oxygen Sensor's life has been consumed.

No, you don't need to remove it from the car in order to reset it. All you need is a sturdy paperclip. In the middle of the right side of the white box, you will find a white disc. There are two holes in this disc that you can shove a paperclip into. Just rotate it clockwise until the counter reset back to "000".

It is not the easiest thing, no. But you're gonna contort to work under the dash anyway, and resetting the counter while leaving it connected is a whole lot less work. It helps to either use a mirror, or an iPhone with the front camera on to act as a mirror so that you can see the meter and verify it rolls back and is zeroed-out.

[vps3922]

All you need is a sturdy paperclip. In the middle of the right side of the white box, you will find a white disc. There are two holes in this disc that you can shove a paperclip into. Just rotate it clockwise until the counter reset back to "000".

Yep, easy to do. Did it with a sturdy paper clip and it works like a charm. My D just turned "30k".

[David T]

Yep, easy to do. Did it with a sturdy paper clip and it works like a charm. My D just turned "30k".

When the light comes on (every 30,000 miles) you are supposed to tune up the car, replace the O2 sensor and adjust the valves. you then reset the counter.

[SoCalDMC12]

Thanks. Odd that it came on at 50k... perhaps I had my 30k done a little early and it was reset then. (I put so few miles on the car that I don't really remember when I had it done.)

[sdg3205]

The lambda counter and odometer aren't quite in sync. I think mine came on 700 miles shy of 30k. There is also the distinct possibility one or the other (or some other part of the system) wasn't working under a PO.