couple of questions concerning my SC

ddwood55

Registered User
I ended up with my son's Thunderbird SC. He wanted a mustang I had in my shop so he talked me into a swap. But anyway it has a couple of problems I was hoping you could help me with.

1. A/C clutch will not engage. I know the clutch is good, but I'm not getting power to it. I have even jumpered the low pressure switch. Any ideas?

2. The antilock and brake lights stay on all the time. The brakes seem fine. The lights were on when my son bought the SC back in 04. Not too long after he bought it he moved to northwest MO so I never got a chance to figure it out. Any ideas on what to look for here?

3. It had the radio with seperate CD player in it originally, both are gone. My son had a pioneer unit and it worked fine. He took it out for the mustang and I went to install an extra radio I had and can't get it to work. I have the plugs wired correctly, the radio comes on but no sound out of the speakers. I figure it has something to do with the premium sound. It has the regular old plug for the power/ground etc.. Then it has two gray cables, one has a 8 pin connector, the other has a 6 pin connector. There is also a red cable with an small black L shape end on it. The only plugs I'm using right now are the plug with the power wires/ ground and the 8 pin which I assume is the speakers. Someone let me know what I'm doing wrong or what I'm missing?

Thanks,
Delos
 
I ended up with my son's Thunderbird SC. He wanted a mustang I had in my shop so he talked me into a swap. But anyway it has a couple of problems I was hoping you could help me with.

1. A/C clutch will not engage. I know the clutch is good, but I'm not getting power to it. I have even jumpered the low pressure switch. Any ideas?

2. The antilock and brake lights stay on all the time. The brakes seem fine. The lights were on when my son bought the SC back in 04. Not too long after he bought it he moved to northwest MO so I never got a chance to figure it out. Any ideas on what to look for here?

3. It had the radio with seperate CD player in it originally, both are gone. My son had a pioneer unit and it worked fine. He took it out for the mustang and I went to install an extra radio I had and can't get it to work. I have the plugs wired correctly, the radio comes on but no sound out of the speakers. I figure it has something to do with the premium sound. It has the regular old plug for the power/ground etc.. Then it has two gray cables, one has a 8 pin connector, the other has a 6 pin connector. There is also a red cable with an small black L shape end on it. The only plugs I'm using right now are the plug with the power wires/ ground and the 8 pin which I assume is the speakers. Someone let me know what I'm doing wrong or what I'm missing?

Thanks,
Delos


(Question) ( 1) The AC clutch will not ingage if system is low on charge did you check that area out as well?


(Question) (2) Brake antilock light stays on you need to bleed the system to re-balance the system out until light goes off
 
question 3, make sure you wire up the blue wire to the harness as well. This wire turns on the amps for the interior speakers as well as the subwoofer if equipped. I had the same problem the other plug is for the cd player and the thick red cable is the ground for the cd player. Not needed and can be left hanging. Also if you want the stock units i have some from my totalled car. Pm to let me know otherwise post back if it works/you need more explanation possibly pics!!
 
(Question) ( 1) The AC clutch will not ingage if system is low on charge did you check that area out as well?


(Question) (2) Brake antilock light stays on you need to bleed the system to re-balance the system out until light goes off

1. With the system discharged, which it is right now, with the low pressure switch jumpered the clutch should engage. I know on every vechicle I've ever had before this would work. I changed compressors due to a bad bearing in the other one. But even with the other compressor and the system fully charged the clutch still would not engage.


2. We have tried bleeding the brakes, starting with the right rear, moving eventually to the left front. Maybe I didn't get all the air out. I'll try again. The lights were on when he bought the car.

Thanks,
Delos
 
question 3, make sure you wire up the blue wire to the harness as well. This wire turns on the amps for the interior speakers as well as the subwoofer if equipped. I had the same problem the other plug is for the cd player and the thick red cable is the ground for the cd player. Not needed and can be left hanging. Also if you want the stock units i have some from my totalled car. Pm to let me know otherwise post back if it works/you need more explanation possibly pics!!


The aftermarket radio I have is a panasonic. It came in a another car I had. It has a solid blue wire which I hooked up and a blue/white stripe which is not hooked up. Maybe I should switch those two wires and see if that works. I'll check it out this morning.

thanks,
Delos

Just went out and checked it. blue/white stripe did the trick. Working fine now, Thanks so much!
 
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On the brakes check the sensor and the ring on the back of the hub. I had a mechanic break both sensors when he dropped the K member.

Ken
 
Here's the ford wiring diagram for the radio system. This is for the JBL w/ cd player, if you have something different, let me know and i'll get the right diagrams :)


radio1.gif


radio2.gif


looks like you need to hook up your Dark Blue wire on the vehicle side to your power antenna/amp turn on wire from the cd player. They're usually blue on the aftermarket head units as well. I ran into this problem back in the day on my tempo which had a factory amp believe it or not, lol.
 
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Hope This Helps

Question #1: The AC compressor clutch is powered and controlled by the Integrated Relay Control Module. That is the black box right behind the passenger headlight. You should check the gray wire with a white stripe for power. If you have no power there, then the IRCM may need to be replaced. The IRCM also controls and powers the cooling fans and the fuel pump.

Question #2: You can take the SC to Autozone or another parts store and have them read the ABS codes. They should be able to tell if it is a wheel sensor or the ABS unit needs to be replaced.

Question #3: I believe Franky_402 has the right answer as I had the same problem. When I connected the BLUE wire, after installing a Sony radio, it worked.

Ed
 
#2 - Can you hear the ABS pump motor turn on from time to time when you step on the brake? It's just a quiet hum, followed by a relay click as it shuts off. It should only do that every once in a while. If it hums every time you step on the brake, then the hydraulic accumulator is not holding pressure and needs to be replaced. It should absolutely not hum all the time.

Also #2 - I don't know what year your SC is, but the 92+ has a different ABS system and the bleeding procedure is different. I am not sure which years the procedure in the link applies to.
 
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Delos,

The clutch was fried on my AC compressor and no matter what I did, even tripping the low pressure switch, made it come on. I had to rap it lightly with a mallet to make it engage.
 
Thanks guys for all the suggestions. You gave me a lot of good places to start.

Mine is a 1990

The clutch was fried on my AC compressor and no matter what I did, even tripping the low pressure switch, made it come on. I had to rap it lightly with a mallet to make it engage.

I borrowed a extra plug off a junker for the A/C and made a jumper. Straight to the battery and to ground. The A/C clutch engaged. Just hit it a few times and engaged everytime. I had already check for voltage at the plug before this and I'm not getting any voltage.

I'll check everything else. Maybe I need to just get my mustang back, not near a much stuff on it! Naw, we made a fair deal, guess I better stick by it. Besides that he would probably tell his mom and I have to live with her!

Thanks again, Y'all have been great!

Delos
 
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