Lambda light 850 t5

[jamie28]

The Lambda light came on yesterday on the motorway ,no running problems and fuel consumption is normal, it might be coincidence but i topped the oil up to max that morning , im going to have a look later at the vacuum hoses etc im wondering what are the commom causes , also will it reset itself if i fix the fault?

[iGGy]

I changed my lambda a few weeks ago and have now had the light come on twice. Like you say, fuel consumption didn't increase on my motorway journey and the car ran fine. The ECU reported fault code 2-1-2, heated oxygen sensor signal absent or faulty. Today I took it out, it's made by Beru and put my old Bosch one back. Not tested it yet as I'm fighting a creak from the top NS suspension mount...all new parts and it creaks!

As it gets logged as a fault in the ECU you need to clear it. Depending on the age of your car it's either via the boxes behind the driver's headlight or the OBD port in the centre console.

Previously I've disconnected to reset the ECU, this doesn't get rid of the light, but supposedly clears the fuel map adaptives. Think I might just see what it does with the old sensor before resetting it.

[jamie28]

thanks for the info , this brings me on to another question are there any reasonably priced code readers/reset tools on the market? or do i have to find a dealer to reset the light? its got the obdII in the car

[iGGy]

Bearing in mind that it's not OBD2 standard compliant, you can do it yourself. Bobcat did a nice howto here http://www.volvo-tech.co.uk/forum/viewtopic.php?t=113

I just stick the wires in the holes and have a switch on flying leads.

[jamie28]

Well after a trip to maplings ive made up a code reader and im getting the fault code 3-1-1 the haynes manual says vehicle speed sensor (speedometer ) signal absent . the speedo works fine and its appeared before so im not to worried.

however code 2- 1- 2 oxygen sensor faulty, also appears i cannot reset the fault and i have cleaned the connector, still no luck.

wheres the best place to get a new oxygen sensor ? and am i correct in thinking there is only one fitted? on the downpipe before the cat?

ps:thanks for the code reader link, thats saved me 50 quid straight away.

james

[jamie28]

[QUOTE=jamie28]Well after a trip to maplings ive made up a code reader and im getting the fault code 3-1-1 the haynes manual says vehicle speed sensor (speedometer ) signal absent . the speedo works fine and its appeared before so im not to worried.

however code 2- 1- 2 oxygen sensor faulty, also appears i cannot reset the fault and i have cleaned the connector, still no luck.

wheres the best place to get a new oxygen sensor ? and am i correct in thinking there is only one fitted? on the downpipe before the cat?

also can the oxygen sensors be bench tested to confirm they have failed?


ps:thanks for the code reader link, thats saved me 50 quid straight away.

[02GF74]

Originally Posted by iGGy

Bearing in mind that it's not OBD2 standard compliant, you can do it yourself. Bobcat did a nice howto here http://www.volvo-tech.co.uk/forum/viewtopic.php?t=113

I just stick the wires in the holes and have a switch on flying leads.

that link does not work - does anyone have a copy that they can post?

Thanks.

BTW the engine lamp has come on (Volvo 850 T5) after a drive through some flooded rods - the water was nowhere deep enough to get into the engine - my best guess is a senor under the car got wet or some steam due to water hitting hot exhaust got drawn into the intake and confused the sensor.

I have not noticed any different in engine performance after the light came on.



just about to investigate.....

[02GF74]

Codes 2-3-1 and 2-3-2, fuel mixture out of spec. Could you caused by intake of water vapour?

I'm unable to clear the fault codes.

Haynes manual states
- lead in A-2
- ignition on
- hold button for 5 sec, the LED should light up after 3 seconds but it doesn't.

Is there a way to reset the codes?