i tried to clear the check engine light but it wont work. i held down the button for 5 sec then i release it waited 3 secs, but when i waited the three secs it either didn't turn on and stay on, which it supposed to, and somtimes it just started blinking. i even tried disconnecting the battery for a long time nothing.

 

What year is your car?
Do you have OBDI or OBDII?
If you have OBDI follow the link and it should help you to clear the CHECK ENGINE LIGHT.
http://www.troublecodes.net/Volvo/
If you have OBDII you will need to have it cleared by a scanner for OBDII

 

my car is a 93 850. and i tried the link it didn't work.

 

The link didn't work or the code didn't clear?
That should have worked to clear the code.

 

the linked worked but to clear the code no. i held it for five sec and it supposed to stay lit, but it didn't. it either doesn't light up or it starts blinking.

 

I went to the Volvo dealer for a recall on the gas tank, and I had the check engine light on because I took the flame trap off, and could not get a new one quickly, and drove the car. Once I replaced the flame trap, the check engine light was still on, and I had a code for the MAF sensor. Anyway, everything with the car was okay, except it was getting too much air, until I replaced the flame trap. The code, however did not clear up, but like I said, I had to take it to the dealer for the recall. I had tried the five second, then wait, then five second, then wait, then press method, and it didn't work for me. Maybe it was because I had some hidden codes somewhere else... like with my abs module. I know that that is bad, but the light does not go on all the time. Anyway, when I went to the Volvo dealer, they cleared the check engine light. I asked the mechanic how to do it, if it happens again, and he said to disconnect both cables from the battery, and touch them together for about 15 seconds, and this will do it. I haven't had the light come on as of lately, but that's what he said.

 

Also you have to make sure you read all the codes first before you can clear them.