Troubleshooting the AC A/C system (fuses, etc)
#31
::CF Administrator::
$20 is a lot cheaper than $400, which is what a Fluke DMM rated for automotive use would cost. Sure you can get DMM's cheaper, but Fluke makes the best. After 25+ years in aerospace electronics manufacturing, a DMM is not a tool I would cheap out on, plus they are serviceable and can be calibrated. Properly used and cared for it will last you the rest of your life...just my .02, I'm sure plenty will disagree
#34
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Year: 1998
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Engine: 4.0L i6
Either you didn't watch the video, or you don't understand what I am trying to do.
To connect the relay to a power source, you just need a lead clamp
It costs $3. Not $400.
I already have a $20 Multimeter which is also connected to the relay
I just need these $2 clips to hook to a power source
http://www.ebay.com/itm/2PCS-Large-s...-/291044635531
http://www.ebay.com/itm/Pair-of-Dual...-/390731785364
To connect the relay to a power source, you just need a lead clamp
It costs $3. Not $400.
I already have a $20 Multimeter which is also connected to the relay
I just need these $2 clips to hook to a power source
http://www.ebay.com/itm/2PCS-Large-s...-/291044635531
http://www.ebay.com/itm/Pair-of-Dual...-/390731785364
Last edited by BimmerJeeper; 12-27-2013 at 06:39 PM.
#35
::CF Administrator::
$20 is a lot cheaper than $400, which is what a Fluke DMM rated for automotive use would cost. Sure you can get DMM's cheaper, but Fluke makes the best. After 25+ years in aerospace electronics manufacturing, a DMM is not a tool I would cheap out on, plus they are serviceable and can be calibrated. Properly used and cared for it will last you the rest of your life...just my .02, I'm sure plenty will disagree
You clearly didn't watch the video.
It costs $2. Not $400.
I already have a $20 Multimeter.
LOL, I love internet forums.
I just need these $3 clips to hook to a power source.
http://www.ebay.com/itm/Pair-of-Dual...-/390731785364
It costs $2. Not $400.
I already have a $20 Multimeter.
LOL, I love internet forums.
I just need these $3 clips to hook to a power source.
http://www.ebay.com/itm/Pair-of-Dual...-/390731785364
#36
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Year: 1998
Model: Cherokee
Engine: 4.0L i6
LOL, do you also tell your mother to buy a Ferrari to drive to church once a week??
I want to test a $10 relay, not change careers, spend $25,000 on Fluke tools and classes, and become an professional electrician.
I don't need a MM, I need test clips that fit onto a car battery.
Please read what I said in post #25
I want to test a $10 relay, not change careers, spend $25,000 on Fluke tools and classes, and become an professional electrician.
I don't need a MM, I need test clips that fit onto a car battery.
Please read what I said in post #25
I am going try to test the relay.
Just need to buy some test leads.
Auto Repair & Mechanics : How to Test a Car Relay - YouTube
Just need to buy some test leads.
Auto Repair & Mechanics : How to Test a Car Relay - YouTube
Last edited by BimmerJeeper; 12-27-2013 at 08:10 PM.
#38
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Year: 2000
Model: Cherokee
LOL, do you also tell your mother to buy a Ferrari to drive to church once a week??
I want to test a $10 relay, not change careers, spend $25,000 on Fluke tools and classes, and become an professional electrician.
I don't need a MM, I need test clips that fit onto a car battery.
Please read what I said in post #25
I want to test a $10 relay, not change careers, spend $25,000 on Fluke tools and classes, and become an professional electrician.
I don't need a MM, I need test clips that fit onto a car battery.
Please read what I said in post #25
#39
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Year: 1998
Model: Cherokee
Engine: 4.0L i6
I replaced my AC Relay with a new one.
AC clutch still doesn't engage.
I can see the bolts in the pulley not spinning.
Just to make sure I'm testing this correctly,
I just turn the HVAC **** to the blue snowflake, and put the temp. dial onto blue.
This should be enough to engage the AC, right?
There is no AC button that some cars have.
AC clutch still doesn't engage.
I can see the bolts in the pulley not spinning.
Just to make sure I'm testing this correctly,
I just turn the HVAC **** to the blue snowflake, and put the temp. dial onto blue.
This should be enough to engage the AC, right?
There is no AC button that some cars have.
#40
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Year: 1999
Model: Cherokee
Engine: 4.0
I replaced my AC Relay with a new one.
AC clutch still doesn't engage.
I can see the bolts in the pulley not spinning.
Just to make sure I'm testing this correctly,
I just turn the HVAC **** to the blue snowflake, and put the temp. dial onto blue.
This should be enough to engage the AC, right?
There is no AC button that some cars have.
AC clutch still doesn't engage.
I can see the bolts in the pulley not spinning.
Just to make sure I'm testing this correctly,
I just turn the HVAC **** to the blue snowflake, and put the temp. dial onto blue.
This should be enough to engage the AC, right?
There is no AC button that some cars have.
Where do you live in the USA? Lower ambient temperatures, below approximately 30°, will cause the low pressure clutch cycling switch contacts to open. This is due to the pressure/temperature relationship of the refrigerant in the system, therefore the clutch won't engage.
Also, the low pressure cycling clutch switch contacts are open when the suction pressure is approximately 20.5 psi or lower. The switch contacts will close when the suction pressure rises to approximately 34 to 38 psi or above, allowing the clutch to engage. Do you know what your suction pressure is?
The low pressure clutch cycling switch is located on top of the AC Accumulator.
#42
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Year: 1999
Model: Cherokee
Engine: 4.0
Here's how to check the clutch if the suction pressure is too low or the ambient temp is too low.
You will be jumpering the two pin cavities in the low pressure clutch cycling switch connector with a paper clip, or equivalent.
Refer to the pic below.
Unplug the connector from the switch. Jump the two pin cavities in the connector with a paper clip. Do not force the paper clip into the pin cavities if they won't go in easily. If necessary, file down the ends of the clip wires so the fit easily, but snugly.
Turn the mode selector to any AC setting (snow flake), turn the ignition switch to RUN (ON), but do not start the engine. The clutch should engage.
Try this and see what you find.
You will be jumpering the two pin cavities in the low pressure clutch cycling switch connector with a paper clip, or equivalent.
Refer to the pic below.
Unplug the connector from the switch. Jump the two pin cavities in the connector with a paper clip. Do not force the paper clip into the pin cavities if they won't go in easily. If necessary, file down the ends of the clip wires so the fit easily, but snugly.
Turn the mode selector to any AC setting (snow flake), turn the ignition switch to RUN (ON), but do not start the engine. The clutch should engage.
Try this and see what you find.
#43
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Year: 1998
Model: Cherokee
Engine: 4.0L i6
Thanks CCKen. Those are very clear directions.
The only problem is that I won't be able to see the clutch engage from inside the car. Not sure if I will hear it.
Before I try this, I will try to push in the clutch with my hand just to see the difference of engaged vs. disengaged.
Then, after I turn the key, I will get out and go look at what state it appears to be in.
The only problem is that I won't be able to see the clutch engage from inside the car. Not sure if I will hear it.
Before I try this, I will try to push in the clutch with my hand just to see the difference of engaged vs. disengaged.
Then, after I turn the key, I will get out and go look at what state it appears to be in.
Last edited by BimmerJeeper; 12-30-2013 at 11:47 AM.
#44
Senior Member
What's the temp there?
If it's under 60-65 then give up.
The A/C isn't designed to work during the winter. Pressures are way TOO low for operation. Refer to a temp/pressure chart. The high cycling of the compressor is due to low pressure such as being too cold.
If it's under 60-65 then give up.
The A/C isn't designed to work during the winter. Pressures are way TOO low for operation. Refer to a temp/pressure chart. The high cycling of the compressor is due to low pressure such as being too cold.
#45
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Year: 1999
Model: Cherokee
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Thanks CCKen. Those are very clear directions.
The only problem is that I won't be able to see the clutch engage from inside the car. Not sure if I will hear it.
Before I try this, I will try to push in the clutch with my hand just to see the difference of engaged vs. disengaged.
Then, after I turn the key, I will get out and go look at what state it appears to be in.
The only problem is that I won't be able to see the clutch engage from inside the car. Not sure if I will hear it.
Before I try this, I will try to push in the clutch with my hand just to see the difference of engaged vs. disengaged.
Then, after I turn the key, I will get out and go look at what state it appears to be in.