Hey there, I got a '96 960 in March and it's in super great shape, which is the only reason I would buy a car this old, but I'm running into my first annoyance.

I have a check engine light that turns on a few seconds after the car starts but there are no codes in the obd2 scanner, I bought my own, no codes, I brought it to autozone, no codes, and my mechanic doesn't get anything either. I even brought it to a volvo mechanic with a special scanner and he didn't get anything, saying it's the first time he's ever(!) seen that happen.

I've also tried disconnecting the battery for a few minutes but it came right back, with no codes.

The last code I had was a few weeks ago when it was still below freezing, my PNP switch was tripping the check engine and flashing "winter mode" arrow. I had my mechanic clear it a few times when one day the flashing arrow went away, but not the check engine light, and a few more weeks later it's still on and nothing I can do will clear it.

Soon I am planning on changing the timing belt and maybe I should also do the PNP switch to see if it will clear it, but in the mean time does anyone know anything about this? I don't want to scan it every week to see if anything REAL actually needs the check engine light.

 

Tough one! CELs are sometimes known to do this and it's "just" an electrical malfunction and it is understandably annoying... It's basically a short in the system but finding it could be time consuming and costly. Sorry, no good answer for that one!

 

I'm by no means an expert, or even know anything. but wouldn't a short of some sort have the light on always? Mine takes a few moments (10ish seconds) to turn on after you turn the car on.

 

Electrical shorts are impossible to predict how they will manifest themselves in the complicated automotive jumble--it could be anything, from a bad ECU to a slight wire chafing or a cracked solder on the back of the circuit board. You can try auto electrical shops to find a solution, sometimes they are able to find things quickly.

 

In my 98 the broken PNP switch set a fault code and made the CEL come on. I don't know if the fault code for the PNP switch was a new thing in the 98 motronic or not.

 

I had the code for the pnp a few weeks ago, I cleared it a few times because I knew it wasn't a huge deal, I just wanted the engine light to turn off. But the strange thing is now I don't get a PNP fault code, but just the check engine light.

Like I said I'll replace the PNP soon (a few weeks still probably) and post here if that fixed it or not.

 

My '95 960 Wagon check engine and SRS lights have been on for years. Too bad I can't use my OBD II reader rather than the archaic prehistoric flashing light port system. Neither condition has caused any performance issues, so I will continue to ignore. It's basically a 3rd car hauler but I am curious as to what the condition is.

 

I just remembered that in some situations the transmission can request the check engine light to come on. Maybe there is a fault code stored in the transmission.

VOL-FCR can read this but there might be a flashing light method too.

 

Wow, same thing on my 1992 960 sedan. I've had ZERO issues yet the engine light keeps staying on.