1996 Mercedes-Benz C280 Q&A

1996 Mercedes-Benz C280 Question: california smog readiness flags

I have a 1996 c280, 165000 miles due for a biannual smog test. If failed the first test due to not all readiness flags not being set. I have taken it to several friends shops( I am a tech myself) and they are unable to get them to set. We have a complete drive cycle sheet showing exactly conditions to set the monitors. We have driven this cycle multiple times and have driven over 2000 miles since then. I have been told it may be the DME. Is there anyway of telling exactly what is at fault without shelling out $2000.? Are DMEs interchangeable from other c280s? Thanks for your help. -
Answer 1
Scantool information should be able to identify which monitors have not passed. Is it Evaporative , EGR, catalytic converter efficiency? I have gotten a lot of cars to pass monitor tests and have friends that are well up on Mercedes problems if you can tell me which monitors presently don't pass. -
Answer 2
I too have a 1996 C280 and its a known issue. You need to take your failed smog test results and have BAR (California Bureau of Auto Repair) Referee center smog it. I've done it for my last 3 smogs. Its something to do with 96 c280s and OBDII. Here's their number for more info. (800) 622-7733 -
Comment 1
Hi there I have a 1996 C280 that keeps getting rejected because the EGR, Secondary Air, and Catalyst Monitors will not set. I have driven the car through the drive cycles, brought it to multiple shops and no one seems to know what is going on with it. I live in las Vegas and apparently i cannot get an exemption unless the car fails the smog and it is just getting rejected because the monitors will not set. PLEASE HELP -