Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help



Go Back   PeachParts Mercedes-Benz Forum > Mercedes-Benz Tech Information and Support > Tech Help

 
 
LinkBack Thread Tools Display Modes
Prev Previous Post   Next Post Next
  #1  
Old 11-20-2002, 01:29 AM
Registered User
 
Join Date: Jul 2002
Posts: 30
W124 O2 Sensor Problem

Here is one for the smart minds: Computer tells me there is an O2 sensor problem. Two codes: 'Incorrect voltage from 02 sensor' and 'Heater amps too high/shorted'.

There is _no_ current to the O2 heater, and a continuity check finds an open circuit from pin 7 of the fuel pump relay, where the schematic says the O2 heater is connected. That would lead me to think there is a break in the wire, but that seems _very_ unlikely.

Meanwhile, the 02 sensor itself is reading only 0.1V, even after being heated up by exhaust. Normally I'd say its a bad sensor, but I just replaced it in April and it has less than 10K miles on it. Its an OEM sensor.

Any ideas? Is there a fuse on the heater wire that might have blown? I didn't see anything during 3+ hours of inspection.

The car is a 93 300E.
Reply With Quote
 

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -4. The time now is 03:07 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2025, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2024 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page