Tell me about code scanners.

[rhombus]

I've got a Check Engine Light that I would like to diagnose. I have a '97 ti, making it OBD-II, so I'm gonna need a scanner, but I don't know much about them.

It appears to me there are a few types. One is a fairly generic OBD-II scanner that plugs in somewhere around the steering column into a standard OBD-II port and works on pretty much any car built after 1995. I've looked at things like Scan Guage II that fall into this category. This would be nice, because in addition to reading codes, it can sit on your dash and act as a trip computer, provide digital guages and other data instantly. The potential downside is that I've read that these type of scanners might not work reliably with our BMWs and I'm not sure if they can reset CELs or things like the oil service indicator.

The other option appears to be the Peake Research scan tool, which plugs into the circular BMW computer port under the hood. It appears to be made exclusively for BMWs and does reset all sorts of lights. To me, that means it should be more reliable, but I have heard of them messing up as well. I had my car into a shop once for a CEL among other things, and they used some very fancy, very expensive BMW code reading computer that plugged into the same port.

My ti didn't come with an on-board computer, so I think it would be great to have something like the Scan Gauge II, but only if it can perform all of the functions that the Peake Research tool can. Please educate me.

[AutoM3otives]

Hey that Scan Gauge II looks pretty cool.

If you're worried about turning off the CEL and resetting the oil lights, no problem. Looks like the SG2 can turn off the CEL based on its description.

As for the oil lights, there is the 'paperclip' trick that you can use to reset. Open up a paperclip and shove both ends into holes 7 & 19 in the circular data link port under the hood. Place the key in the ignition and turn it to the ON position. The strip of green lights should all illuminate. Wait about 5 seconds, until all the green lights go out. Remove the key from the ignition, remove the wire, and replace the cap.

[rhombus]

Originally Posted by AutoM3otives

Hey that Scan Gauge II looks pretty cool.

If you're worried about turning off the CEL and resetting the oil lights, no problem. Looks like the SG2 can turn off the CEL based on its description.

As for the oil lights, there is the 'paperclip' trick that you can use to reset. Open up a paperclip and shove both ends into holes 7 & 19 in the circular data link port under the hood. Place the key in the ignition and turn it to the ON position. The strip of green lights should all illuminate. Wait about 5 seconds, until all the green lights go out. Remove the key from the ignition, remove the wire, and replace the cap.

I think someone around here has a Scan Gauge II, but I can't find the thread where I read about it. I think it was about water wetter... Anyway, I'll look harder and try and get them to come to this thread and post about it.

The paperclip trick sounds cool. I just got the car and they reset the oil light for me at the shop when I brought it in right after I bought it, so it hasn't been a problem yet, but it will be in the future. I haven't looked at the under hood port very closely, but are all the pin holes numbered, or will I need to print out a sheet to help me find holes 7 and 19?

[AutoM3otives]

The holes have a number 'engraved' next to each of them. You can barely see them in this pic, but once your up close, you can make them out.

You'll have to do a quick run-thru of all the holes and numbers to make sure which number corresponds to each hole just so that you don't put the clip in the wrong hole.

Other than that, its cake.

[zboot]

our 318tis use the ISO9141 protocol. Just make sure the scanner supports ISO and you should be fine. Access to some features is tied to the VIN number of the car. Some scan tool makers design their tools or software so that you can't do things like reset CELs unless the tool reads the VIN number correctly or you enter it in. Typically, the tool (or software) will prompt you if it's unable to detect or get the infotype successfully from the vehicle ECUs.

[bullmand]

I have the ScanGauge. So far I've been very happy with it. It works as advertised for monitoring certain engine parameters(it won't display manifold absolute pressure or fuel pressure on my car), the fuel economy tracking is dead on. It's learned enough to tell me exactly how much gas I need to fill the tank up. As for the code scanning, I've only had one code since I got it and that was the "dumbass" code (fuel filler cap loose). It only outputs the code in numerical format(Pxxxx), so you still have to look it up on the web. I don't know how it will handle BMW specific codes as I haven't had one yet. It reset the fuel cap code with no problems. Best part: you can change the display color to very closely match the car's instrument lighting. Overall I'm very happy with it. Hope this helps.