how would I check the codes on my 1986 volvo 740gle b230f. And also how would I reset them.
Thanks.

 

Unfortunately you can't. OBD1 was not fitted until the 1989 model year.

 

so how would I find out why the engine light is on?

 

I really don't know anything about the model year of your car so I searched ALLDATA and they stated that the only thing that is monitored is the ignition system and thata Volvo Diode tool has to be used to get the flashes to correspond to the problem. The good thing is there are only a couple of things that can cause the problem so it may help to narrow it down without going to Volvo. Here's a cut and paste from Alldata.

 

thanks a million that helps alot the car was boggy and undriveable sence I got it. I got it for free because of that. when I got it I fixed the wireing abit and replaced the AMM that made her driveable but the engine light was on so i thought something else might be gon bout now i think it is the knock sensor wireing.

 

You can unhook your battery cables for a half hour or so and this will clear your codes and turn off the engine light. Of course it erases your radio settings too but it's an easy way of clearing out the ECU if you don't have the reader tool.

 

I got it FIXED!!!!! i olny fixed half the wireing when i got it and as i ws fixing it i noticed that the wires that were incased in the plastic were good so i never bothered to look at the rest them but today i striped out the whole wireing harnes and striped off all the covering and found 2 wires shorting out and taped every bad wire up then put it back in now it purs like a kitten...if a kitten had no mulfer. cant weight tell 4 more years then I can drive her legealy. hehe lol i am 14 and got a 1986 volvo, 1987 subaru, 1986 dodge caravan with a mitsubishi engine, and a 1971 vw superbeatle. I Love Imports
and thanks again if you never showed me that i would never checked the wireing again.