Code Scanner Question

[spireview]

I have the dreaded "blinking O/D" light and was going to invest in a scanner for my 99 XLS to try an diagnose it. I think i've read every "blinking" post, but I'm still a little confused on the scanner. Someone mentioned that I wouldn't be able to read what code the tranny was throwing because it was related to the GEM and a simple OBDII scanner can't read those codes....so would i be wasting my money if I purchased a ~$100 scanner to diagnose this problem?

If not, what scanner do you recommend? I also have a 96 Outback and 05 MDX, so it would be nice is the suggested scanner could read those codes too.

 

[Glacier991]

An OBD-II Scanner should read all generic transmission codes. (the p0700's). The question is when there is a proprietary code set (p1700's) will it be able to read those?

Your question is better posed in the Under the Hood Forum in the Computers section, and so I am going to take the liberty to move it there. There are discussions of scanners that should help you.

 

[ExplorerDMB]

The GEM and transmission hardly have anything to do with each other. The Explorers usejust one ECU/PCM to communicate to the engine and transmission. You should be able to get your code via scanner.

-Drew

 

[glfredrick]

The big problem with the cheapy ($100) scanners you mention is that they ONLY read codes. That is really no help at all, for the codes seldom are the real problem, nor do real problems always set codes. You can have a hole in the side of the block and set zero codes.

I recommend a higher level diagnostic tool like the Snap On Heritage Scanner. It at least lets you see all the actual data that your PCM/ECM is sending and recieving including the transmission. It also lets you turn on and off all the various electronically controlled things on your vehicle, including operating any electronic transmission valves and solenoids.

Yes, it is a lot of money, but it is also about the only real way to diagnose.

Note: For the naysayers out there, I dare you to actually diagnose a modern computer controlled vehicle using a simple code reader -- it cannot be done. For instance, an oxygen sensor code doesn't mean that the oxy sensor is bad -- it just means that it is getting an out of spec reading. Is it bad or not? How do you know? How many times do you have to replace $75 ECM parts to figure it out? Scanners are out there on eBay for under a $1000 and you can get upgrades from Snap On all the time. Then add a Vantage to your arsenal and REALLY do diagnostic work. It tests individual components to see if they are working, something even the scanner cannot do.