How do I retrieve diagnostic trouble codes when there is a check engine light illuminated?

Chris

Chris

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If your TJ has a check engine light illuminated, below is the procedure for retrieving the diagnostic trouble code(s):
  1. Turn the ignition key until the digital odometer displays, then turn it back to off. Repeat three times in succession. (ON/OFF/ON/OFF/ON)
  2. Count the number of times the check engine light on the dash flashes on and off. The number of flashes represents the trouble code. There is a slight pause between the flashes representing the first and second digits of the code. Longer pauses separate different trouble codes.
  3. For example, light flashes 5 times, then a short pause, then flashes 5 more times. This is code 55.
  4. Diagnostic trouble codes will also be shown in the odometer display.
  5. Code 55 is the last diagnostic trouble code displayed.
  6. See below for list of diagnostic trouble codes.
Note: This procedure does not work on 1998, 1999 and some 2000 model TJs.

For an easier way to read error codes on your TJ, I highly suggest purchasing the Launch cReader OBDII scanner. I have one of these personally and absolutely love it. It's easily one of the most affordable, easy to use and intuitive OBDII scanners out there. It will also work on pretty much any vehicle as well.
 
If you go to Harbor Freight they have a scan tool that is usually on sale. Does a great job and will also tell you after you have fixed the problem(s) when the systems is ready for emission testing. It will also to freeze frame diagnostics and show you what was going on when the code was set. Normally $80 I've seen it as low as $60.
 
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I purchased the Launch cReader VI+ a few years ago from Amazon. I bought it because I needed an OBDII diagnostics tool for my TJ, but figured it would also be helpful for other vehicles we own as well.

Anyways, after several years of owning this I'm very happy to report that for the price this thing is absolutely amazing. Full color LCD display, super easy to understand interface, live diagnostics, built in codes (and descriptions of the codes and what they mean) for almost every make and model of modern vehicle from Jeep to BMW, etc.

If you're looking for a diagnostic tool but don't want to spend a ton of money, I seriously can't recommend this thing enough. It's become a toolbox staple of mine.

Anyways, here it is:
http://www.amazon.com/gp/product/B00CP8CV7U/?tag=wranglerorg-20
 
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Chris said:
If your TJ has a check engine light illuminated, below is the procedure for retrieving the diagnostic trouble code(s):
  1. Turn the ignition key until the digital odometer displays, then turn it back to off. Repeat three times in succession. (ON/OFF/ON/OFF/ON)
  2. Count the number of times the check engine light on the dash flashes on and off. The number of flashes represents the trouble code. There is a slight pause between the flashes representing the first and second digits of the code. Longer pauses separate different trouble codes.
  3. For example, light flashes 5 times, then a short pause, then flashes 5 more times. This is code 55.
  4. Diagnostic trouble codes will also be shown in the odometer display.
  5. Code 55 is the last diagnostic trouble code displayed.
  6. See below for list of diagnostic trouble codes.
Note: This procedure does not work on 1998, 1999 and some 2000 model TJs.
Click to expand...

On my 97, I have to hold my trip reset button down while I do the on/off thing.
 
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Chris said:
I purchased the Launch cReader VI+ a few years ago from Amazon. I bought it because I needed an OBDII diagnostics tool for my TJ, but figured it would also be helpful for other vehicles we own as well.

Anyways, after several years of owning this I'm very happy to report that for the price this thing is absolutely amazing. Full color LCD display, super easy to understand interface, live diagnostics, built in codes (and descriptions of the codes and what they mean) for almost every make and model of modern vehicle from Jeep to BMW, etc.

If you're looking for a diagnostic tool but don't want to spend a ton of money, I seriously can't recommend this thing enough. It's become a toolbox staple of mine.

Anyways, here it is:
http://www.amazon.com/gp/product/B00CP8CV7U/?tag=wranglerorg-20
Click to expand...

I only find this from one seller at $140. Is that what you paid? If not do you have another recommendation? Looking at that Ultragauge.
 
I found an $18 one on Amazon similar to the one referenced by @Chris above and keep it in the glove compartment, have used it many times to reset the codes as well as successfully diagnosing 2 bad O2 sensors...paid for it'self in spades already.
 
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cliffish said:
Yep that is the one I use as well..OK it increased a buck from when I bought it.
Click to expand...

Yep, it's handy. I can just keep it in the glovebox, and since I already have my phone on me anywhere I go, it means I don't have to worry about not having a scanner on me. I bought one for each of our vehicles to keep in the glovebox. I'm sure one day it will pay for itself.
 
Chris said:
Yep, it's handy. I can just keep it in the glovebox, and since I already have my phone on me anywhere I go, it means I don't have to worry about not having a scanner on me. I bought one for each of our vehicles to keep in the glovebox. I'm sure one day it will pay for itself.
Click to expand...
You have a TJ of course it will pay for itself soon enough.
 
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cliffish said:
You have a TJ of course it will pay for itself soon enough.
Click to expand...

Oh don't worry... it only gets driven like 1000 miles a year.

I'm in that very awkward stage of life... you know, the one where you have a newborn, a 3 year old, and a 6 year old.

I never used to believe people when they would tell me that they had to give up their toys because their kids took up so much time until they got a bit older. I get it now though, 100%!

With one kid it wasn't that big of a deal, but with 3... you can bet that my time is limited ;)
 
Chris said:
Oh don't worry... it only gets driven like 1000 miles a year.

I'm in that very awkward stage of life... you know, the one where you have a newborn, a 3 year old, and a 6 year old.

I never used to believe people when they would tell me that they had to give up their toys because their kids took up so much time until they got a bit older. I get it now though, 100%!

With one kid it wasn't that big of a deal, but with 3... you can bet that my time is limited ;)
Click to expand...
My kids are 17 and 20...it does not get any better. I was physced I pu 4K on my TJ in it's first year....but my Corvette, less than a 100 and my TR6, I think I backed it off the lift twice, not sure it ever left the driveway.
 
cliffish said:
My kids are 17 and 20...it does not get any better. I was physced I pu 4K on my TJ in it's first year....but my Corvette, less than a 100 and my TR6, I think I backed it off the lift twice, not sure it ever left the driveway.
Click to expand...

I get it though... you just have it there for those super rare occasions where you get a few hours all to yourself and get to take it out and enjoy it.

I have one of those days coming up in 2 months where my wife is taking the two young ones out of town for the weekend. I’ll get to take my eldest out with me, but she will enjoy it if it’s just her and I.
 
the real issue as far as the vett and tr6 is during the week...I am constanly throwing boxes in my car and that makes them prohibitive M-F. At least the TJ can handle a few boxes.
 
I'm in the opposite boat. My son's 18. And leaves again tomorrow morning at 4am for college in New York. What I wouldn't give to have more time with him. But I remember those days of remembering when I was young. And thought I was sooooo busy. lol. Fatherhood kicks "I'm too busy's." ass. :)

Thanks so much for posting that device. Perfect for what I need.
 
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