YACT: check engine light?

[Shelly21]

One of the cars that I drive is a 94 Jeep Grand Cherokee Laredo, Recently, the check engine light will light up whenever I use air condition, (and this morning, heat). Do you guys know what could be causing it?

FYI, I just changeed my own oil, and I use Valvoline Maxlife.




Everything just keeps on breaking recently, my downstair air condition unit is not working ever since the hurricane. the circuit breaker is tripped and will not "untrip", I guess I'll have a man look at it.

 

[Eli]

Hmmm.

Only when you use A/C or Heat?

Does it turn off when you shut said items off?

*boggle*

I'll let someone else chime in on this one.

Of course, if you want a generic suggestion.. take it to a mechanic and reproduce the problem for them. They'll either know, or can pull the codes and find out.

 

[Mr N8]

Take it to Autozone, or a similar store when the check engine light is on. Most parts stores have a diagnostic computer that will give you the code. Of course, they will try to sell you the parts to fix it, but at least you will have an idea of what the cause is.

 

[iamwiz82]

check the codes by putting the key in the ignition and cycling it five times, off - on - off - on - off. DO not start the car, just go to the on position, where the radio/lights, instrument panel turn on. The check engine light will flash a certain number of times. It will flash quickly(this represents tens), then pause and then flash again(this represents ones). This is a code. Count the number of flashes the first time(lets say it goes flash flash flash), this stands for 30. Now it will pause, signalling that the ones are next and will flash again. flash flash flash flash flash flash would be 6, so the code is 36. This will keep happening for every code and will end with 55.

Once you have the codes they can be looked up online

 

[StageLeft]

Another vote for taking it to autozone for free diagnostic.

 

[Mr N8]

Originally posted by: iamwiz82
check the codes by putting the key in the ignition and cycling it five times, off - on - off - on - off. DO not start the car, just go to the on position, where the radio/lights, instrument panel turn on. The check engine light will flash a certain number of times. It will flash quickly(this represents tens), then pause and then flash again(this represents ones). This is a code. Count the number of flashes the first time(lets say it goes flash flash flash), this stands for 30. Now it will pause, signalling that the ones are next and will flash again. flash flash flash flash flash flash would be 6, so the code is 36. This will keep happening for every code and will end with 55.

Once you have the codes they can be looked up online

Does this work on all GM cars?

 

iamwiz82 hit the nail on the head, turn your ignition "on and off' three times in a row without starting the vehicle, watch your check engine light, it will start blinking in codes, write these codes down and click here to see what those codes are.

Does this work on all GM cars?

Please state make, model and year of vehicle please.

Here's 20 bucks it's a code 33

 

[iamwiz82]

Originally posted by: MogulMonster

Originally posted by: iamwiz82
check the codes by putting the key in the ignition and cycling it five times, off - on - off - on - off. DO not start the car, just go to the on position, where the radio/lights, instrument panel turn on. The check engine light will flash a certain number of times. It will flash quickly(this represents tens), then pause and then flash again(this represents ones). This is a code. Count the number of flashes the first time(lets say it goes flash flash flash), this stands for 30. Now it will pause, signalling that the ones are next and will flash again. flash flash flash flash flash flash would be 6, so the code is 36. This will keep happening for every code and will end with 55.

Once you have the codes they can be looked up online

Does this work on all GM cars?

You mean chrysler. No, not all. They have changed the standards quite a few times over the years. This will work on a 94 Grand Cherokee, though. Some require you to hold the odo reset button.

 

[TEEZLE]

Originally posted by: Skoorb
Another vote for taking it to autozone for free diagnostic.

I third that. Took my car in with a emissions light and I had a bad EGR valve. I replaced it but my light came back on 1 day after it was reset?! Might be a sensor problem?

Oh yeah go to AutoZone!!

 

[Shelly21]

Now, that trick with the turning the key on and off, it will only work if the check engine light is constantly on right?

The check engine light will only come on after I turn on the air conditioning unit, and will not go away after I turn the air conditioning unit off. However, If I shut off my engine, and start it up again, the check engine light will go away.


I think the best idea might be just taking it to the Autozone when the light comes on and have them pull the code off. Thanks guys. :music:

 

[conjur]

Originally posted by: iamwiz82

Originally posted by: MogulMonster

Originally posted by: iamwiz82
check the codes by putting the key in the ignition and cycling it five times, off - on - off - on - off. DO not start the car, just go to the on position, where the radio/lights, instrument panel turn on. The check engine light will flash a certain number of times. It will flash quickly(this represents tens), then pause and then flash again(this represents ones). This is a code. Count the number of flashes the first time(lets say it goes flash flash flash), this stands for 30. Now it will pause, signalling that the ones are next and will flash again. flash flash flash flash flash flash would be 6, so the code is 36. This will keep happening for every code and will end with 55.

Once you have the codes they can be looked up online

Does this work on all GM cars?

You mean chrysler. No, not all. They have changed the standards quite a few times over the years. This will work on a 94 Grand Cherokee, though. Some require you to hold the odo reset button.

I thought that only worked on '96 and newer...the ones with OBD II.

 

Shelly, it's not a trick, this is how you pull the codes on Chrysler vehicles, this will work anytime, anywhere, even if you never saw the check engine light come on at all.

I thought that only worked on '96 and newer...the ones with OBD II.

No,no,no !

OBD II requires a code reader, only the older Chryslers have this type of system.

 

[iamwiz82]

Originally posted by: Roger
Shelly, it's not a trick, this is how you pull the codes on Chrysler vehicles, this will work anytime, anywhere, even if you never saw the check engine light come on at all.

I thought that only worked on '96 and newer...the ones with OBD II.

No,no,no !

OBD II requires a code reader, only the older Chryslers have this type of system.

Roger, you can pull codes off newer Chryslers also. For a few years there was no way to, after the implemented the digital odometers, but i think by around 99 it was back. My 99 Cherokee and 2000 Neon work by holding the trip reset button while turning the key to on. They are displayed on the digital odometer.

 

Roger, you can pull codes off newer Chryslers also. For a few years there was no way to, after the implemented the digital odometers, but i think by around 99 it was back. My 99 Cherokee and 2000 Neon work by holding the trip reset button while turning the key to on. They are displayed on the digital odometer.

Yes I know, but this does not allow access to all the codes, only the ones that will trip the ECM into "failsafe or Limp Home" mode, this is why I never use that method, I always use my Master tech diagnostic scanner

 

[XZeroII]

Originally posted by: Shelly21
Now, that trick with the turning the key on and off, it will only work if the check engine light is constantly on right?

The check engine light will only come on after I turn on the air conditioning unit, and will not go away after I turn the air conditioning unit off. However, If I shut off my engine, and start it up again, the check engine light will go away.


I think the best idea might be just taking it to the Autozone when the light comes on and have them pull the code off. Thanks guys. :music:

The computer stores the code so the light doesn't need to be on at the time.

 

[conjur]

Originally posted by: iamwiz82

Originally posted by: Roger
Shelly, it's not a trick, this is how you pull the codes on Chrysler vehicles, this will work anytime, anywhere, even if you never saw the check engine light come on at all.

I thought that only worked on '96 and newer...the ones with OBD II.

No,no,no !

OBD II requires a code reader, only the older Chryslers have this type of system.

Roger, you can pull codes off newer Chryslers also. For a few years there was no way to, after the implemented the digital odometers, but i think by around 99 it was back. My 99 Cherokee and 2000 Neon work by holding the trip reset button while turning the key to on. They are displayed on the digital odometer.

Hmm...I read on a Chrysler Sebring forum about doing the on-off method but I couldn't get it to work. I'll try the rest button method then.

 

[Shelly21]

Cool, I learn something new everyday, I'll try that "technique" and pull the code off...

now, where can I deciper this code on line? anyone got a link?

 

I already gave you the link, look up ^^^^

 

[Quixfire]

Originally posted by: Roger
click here to see what those codes are.
Here's 20 bucks it's a code 33

You mean like the one Roger posted?

 

[Shelly21]

ooops, I stand corrected.

 

[Hammer]

its almost winter. just don't use the a/c. problem solved.

 

[PG]

Originally posted by: Hammer
its almost winter. just don't use the a/c. problem solved.

She said it happens with heat too so it needs to be fixed.

 

[ThePresence]

Would this on-off trick work with my 2000 Maxima?

 

[Eli]

Originally posted by: ThePresence
Would this on-off trick work with my 2000 Maxima?

Inferring from the thread, it sounds like it's a Chrysler thing.