99tahoeinwv

hey guys, new to this forum and to chevys. i just bought a 99 tahoe, today as i was driving the service engine soon light came on. went to advanced auto parts and they ran the scanner on it and it came up as bank 2 sensor 2. so its the one after the cat on the pass side. so i got the sensor and replaced it. but when i started the truck up, the light is still on. so i disconnected the negative on the battery and its still on. any thoughts? does it have to be shut off by the scanner? any help would be appeciated. looking forward to this new truck

shamrock246

it has to be cleared with a scanner or i believe if it goes thru a certain amount of succesfull warm up cycles with out a problem the computer will clear the code itself

99tahoeinwv

Any ideas how many starts it will take to turn it off? Thanks for the input

EinST

What exactly was the code? Disconnecting the battery on the 1999 Tahoe should have turned off the MIL. It's possible that the replacement sensor is defective (I've seen one that was clearly dropped, even) or the original sensor wasn't the culprit.

99tahoeinwv

The code was p0161. I was wonderinf the same thing as to whether it was the sensor also. Gonna have them run it again today and see what happens

99tahoeinwv

Another question.. does the service light on chevys come on when its time to do oil or any scheduled maintance? The truck is getting ready to hit 150k miles.

EinST

That code says the sensor took too long to go active and thus the heater circuit malfunction is suspected. Take the connector off the sensor and then verify ground on the BLK wire and battery voltage on the PNK wire with key on. As for service reminders, I don't think they even had the oil life monitor function for the 1999.

99tahoeinwv

Got it shut off.. just needed reset by a scanner. But thanks for all the help guys!

EinST

Glad to hear. Thanks for the update.