Civic 2003 sedan a/c wont start? Where is ECM

[darksniperx]

Describe how you are testing voltage at fuses 1 and 4.

Does the radiator fan ever run?

When you jumped the condenser fan and compressor clutch relays, what specific terminals did you jump?

On top of the fuses there are metal pins, I have connected the multimeter black cable to one pin and the red cable to the other while setting the multimeter to DC.

Regarding relays, if you look from the left hand side of each relay, the first left pin and the one next to is the one I jumped for each relay.

 

[RonJ]

On top of the fuses there are metal pins, I have connected the multimeter black cable to one pin and the red cable to the other while setting the multimeter to DC.

No, that's incorrect. Touch the red wire probe to one fuse tab and the black wire probe to body ground, such as a clean metal part of the engine or even the negative battery post. Measure voltage like this at both fuse tabs.

Regarding relays, if you look from the left hand side of each relay, the first left pin and the one next to is the one I jumped for each relay.

Based on the diagram below, which terminals did you jump?

 

[darksniperx]

I have tested the fuses again.

With the car running, output is 14.6V
With the car not running, the output is 13.3V


Relays, I have jump-wired the 2 red pins, #1 and #2

 

[RonJ]

I have tested the fuses again.

With the car running, output is 14.6V
With the car not running, the output is 13.3V

Relays, I have jump-wired the 2 red pins, #1 and #2

Together, the information says that fuse 1 is good and gets power from the battery.

-------------------------
Do you get the same result if you jump #3 to #1 in each relay and then start the engine?

Do you measure battery voltage at each test tab of 10A dash fuse 14 with the key in ON(II)?

 

[darksniperx]

Together, the information says that fuse 1 is good and get power from the battery.

I know but a/c still wont start.

 

[RonJ]

I know but a/c still wont start.

See additional questions in my edited post above.

 

[darksniperx]

ok, I'll try it out, and get back to you!

 

[darksniperx]

I did jump wired #1 and #3, the is no effect.

I cant check the voltage on fuse #14, dont have a long enough cable, will buy it tomorrow.

 

[RonJ]

I did jump wired #1 and #3, the is no effect.

Jumping 1 to 3 should yield the same result as jumping 1 to 2. Check whether 10A dash fuse 14 is blown or replace it with a known good fuse to see whether it blows when the A/C is turned on. If fuse 14 does not blow, try the jumping 1 to 3 test again.

 

[darksniperx]

Jumping 1 to 3 should yield the same result as jumping 1 to 2. Check whether 10A dash fuse 14 is blown or replace it with a known good fuse to see whether it blows when the A/C is turned on. If fuse 14 does not blow, try the jumping 1 to 3 test again.

Hi fuse 14 is not blown, I have tested, the problem is that there is nothing coming in to #3, when I checked the voltage #3 with ground, its empty.

I have just found a long enough wire and tested the voltage on fuse 14, when the key position is on #2, I get 12.5V

 

[RonJ]

Hi fuse 14 is not blown, I have tested

Did you test BOTH fuse test tabs. Both should have voltage with the key in ON(II).

, the problem is that there is nothing coming in to #3, when I checked the voltage #3 with ground, its empty.

Did you test relay terminal #3 for voltage with the key in ON(II)? Does relay terminal #2 have voltage with the key off or on?

 

[darksniperx]

Did you test BOTH fuse test tabs. Both should have voltage with the key in ON(II).

Yes just tested with long wire, both of the have 12V.

Did you test relay terminal #3 for voltage with the key in ON(II)? Does relay terminal #2 have voltage with the key off or on?

#3 has negative voltage when the car is off
#3 has no voltage when the car is on.

#4 has positive voltage when the car is on
#4 has no voltage when the car is off

#1 has positive voltage when the car is on

I have looked the electric diagram from the same book, and it sais that ECM is suppose to give negative voltage for #3, that is the thing I am trying to find and test.

 

[RonJ]

#3 has negative voltage when the car is off
#3 has no voltage when the car is on.

#4 has positive voltage when the car is on
#4 has no voltage when the car is off

#1 has positive voltage when the car is on

I have looked the electric diagram from the same book, and it sais that ECM is suppose to give negative voltage for #3, that is the thing I am trying to find and test.

Are we looking at the same circuit diagram (see below)?

With the relay removed from the hood fuse box, the receptacle in the hood fuse box for relay terminal #2 should be hot always and for relay terminal #3 should be hot only with the key in ON(II). The receptacles in the hood fuse box for relay terminals #1 and #4 should never have voltage.

Please test each of the four relay receptacles individually and post the results.

Explain what you mean by positive and negative voltage in your tests.

Finally, again, please mention whether you measure voltage at BOTH top test tabs at the fuses you have tested.

 

[darksniperx]

Are we looking at the same diagram (see below)?

With the relay removed from the hood fuse box, the receptacle in the hood fuse box for relay terminal #2 should be hot always and for relay terminal #3 should be hot only with the key in ON(II). The receptacles in the hood fuse box for relay terminals #1 and #4 should never have voltage.

Please test each of the four relay receptacles individually and post the results.

Explain what you mean by positive and negative voltage in your tests.

Finally, again, please mention whether you measure voltage at BOTH top test tabs at the fuses you have tested.

Hi,

Yes, it is the same diagram.

Battery positive negative voltage:

Negative(ground) is when (-) is connected to battery.
Positive(+) is connected to battery.

Clutch relay 4 pins:

Car is ON:

#1+ 14v
#1-
#2+
#2- 14v
#3+
#3-
#4+
#4- 14v

Car is OFF:

#1+ 14v
#1-
#2+
#2- 14v
#3+
#3-
#4+ 14v
#4-

I will test other relays tomorrow, as it is getting later here.

 

[RonJ]

Hi,

Yes, it is the same diagram.

Battery positive negative voltage:

Negative(ground) is when (-) is connected to battery.
Positive(+) is connected to battery.

Clutch relay 4 pins:

Car is ON:

#1+ 14v
#1-
#2+
#2- 14v
#3+
#3-
#4+
#4- 14v

Car is OFF:

#1+ 14v
#1-
#2+
#2- 14v
#3+
#3-
#4+ 14v
#4-

I will test other relays tomorrow, as it is getting later here.

I have no idea what, why, or how you are doing the voltage tests, and you are not directly answering my questions. This is preventing me from helping you. The tests I am suggesting you do are quite simple, and if you provide clear answers, the problem can be pinpointed.

 

[darksniperx]

I have no idea what, why, or how you are doing the voltage tests, and you are not directly answering my questions. This is preventing me from helping you. The tests I am suggesting you do are quite simple, and if you provide clear answers, the problem can be pinpointed.

Hi,

To make it simple, I am going to take a picture of under the hood relay box, and label it there.

 

[darksniperx]

Hi,

Can you tell me one thing, is the ECM -> the ECU which is the onboard computer? Which is located under the glove compartment.

I just looked at the diagram again, and it seems that my radiator fan doesn't work either?

What can I do to be sure to test my radiator fan to be sure that it works or not? If it doesn't work, then it means I cant even drive my car.

 

[RonJ]

Hi,

Can you tell me one thing, is the ECM -> the ECU which is the onboard computer? Which is located under the glove compartment.

I just looked at the diagram again, and it seems that my radiator fan doesn't work either?

What can I do to be sure to test my radiator fan to be sure that it works or not? If it doesn't work, then it means I cant even drive my car.

Again, if you really want help, directly and clearly answer ALL of the questions I have asked in my previous posts. Otherwise, we'll continue to make absolutely no progress in this thread. I don't think you understand the circuit diagram, so you should also just do the tests I have suggested and report the results.

ECU = ECM = behind the passenger kick panel

 

[darksniperx]

Hi,
Can you give me an example on how you want me to show you the results, and i will try to show them to you that way. if you could give me an example.

 

[uberino]

Honda civic 2003 Ex Ac not working

Hi Ron,
I have a Honda Civic 2003 and the ac does not work. The heater works fine though. I took it to pepboys to diagnose the problem and they said it was a bad thermal switch because the compressor wasn't getting any power and did not engage when the ac button was pressed but the ac guy checking it didn't seem to know what he was doing. I have done the basic test but the recycle button does not blink.
Please tell me what to do as i'm a newbie at this.
Thanks