[rickreeves1]

Background:
I have a 1st Gen 2000 Nissan frontier 4cyl 5spd. 75% of the time the AC would blow cold air. Occasionally the AC would stop blowing cold. After reading through several threads I discovered that the Thermal Control Amp is known to go bad on a few Nissan models from the earlier years. I ordered a new Thermal Control Amp from Courtesy Parts. Here is the link Nissan Parts, NISMO and Nissan Accessories - Courtesyparts.com. I read that there is a two wire and three wire version of this part. Please confirm which part you need before ordering.

This is the troubleshooting guide for the Thermo Control Amp from the Service Manual.

This is the location of the Thermal Control Amp as shown in the Service Manual.

Here is the part I received.

The only tools needed were a philips screw driver and a flash light. Here is the Thermal Control Amp unpackaged.

The first thing you must do is remove the glove box. There are a total of six screws holding the glove box on. Remove the two bottom screws here.

Remove the two top screws here.

The two latch screws are the last two holding on the glove box. You may want to support the glove box with one hand while removing these.

The glove box should now be free to remove.

Find a place to sit it on the side along with the screws so that they don't get misplaced.

The Coolant Unit Case should now be easily accessable.

Here you can see the old Thermal Amp Connector.

Remove the thermal Amp Connector by pushing in on the clip and pulling down. Be carefull not to force things here or it may break.

Remove the old Thermal Control Amp from the Cooling Unit Case by pulling down while lifting the top away from the Cooling Unit Case. Again be carefull not to force it too much or it may break.

You must now open the Cooling Unit Case to get to the old Thermal Control Amp. There are five screws holding the bottom of the case on. The bottom left screw is hidden and harder to access. First remove the four screws easiest to access.

Here is a picture of the hidden screw from below. It can be accessed with a long philips screw driver.

I did not completely remove the bottom of the Cooling Unit Case but I was able to finish the job through the space available. You may want to get a long needle nose pliers or some type of grabber tool to remove any built up leaves and debris.

There is an Evaporator Core inside the Cooling Unit Case that has fins and looks similar to a radiator. Here you can see the old Thermal Control Amp sticking in the side of the Evaporator Core. I squeezed the blue flashlight between the top and bottom half of the Cooling Unit Case to keep it open and illuminate the inside.

I was able to squeeze a few fingers inside the Cooling Unit Case to remove the old Thermal Control Amp from the Evaporator Core. The long plasitc piece protruding from the side of the Thermal Control Amp sticks in between the Evaporator Core fins. Grab the old Termal Control Amp and pull it to the left to remove it from the fins.

It is now time to install the new Thermal Control Amp. Once you have it inside the Cooling Unit Case try to stick the protruding plastic piece between the Evaporator Core fins. It will take a little time and patience. I was not able to get it installed as far back as the origional Thermal Control Amp. Hopefully that will not matter.

The new Thermal Control Amp is now installed. Feed the extra wire out the notch in the case.

Install the new Thermal Control Amp into the clip on the bottom of the Cooling unit case. Plug the bottom wire harness into the new Thermal Control Amp. You can use a little electrical tape to keep the excess wires safe.

Repeat the Glove box removal steps from above to reinstall the glovebox. All Done!

So far this fix seems to have corrected my problem. Time will tell. Now someone please go make this a sticky. Feel free to add comments, suggestions, complaints, etc..

 

[joefrontier2]

nice very well done.

 

[nottheiceman]

thanks

Replaced my compressor last year but i know this will be coming soon, thanks for the pics and info. i'm is still good at 150000k miles but i know i will be doing this soon. thanks

 

[PGer555]

Thank you for the write up. I have had this problem for at least 2 years now. Never took the time to change it, but now there is a step by step i have no excuses.

 

[rickreeves1]

Thank for the nice comments.

Update: This seems to have solved my problem. The AC is still working perfectly today.

 

[margaritaphil69]

TCA Replacement

Thanks for the great tutorial. Finished the install on my '02 Frontier. Needed some special long pliers to reach the TCA but not too tough. AC worked great for the first day although it wasn't very hot in the cab. I'll follow up after testing on a hot day and running for a few days.

 

[Gregg the G]

EXELENT Write up

 

[munzo]

thank you for the write up! I am pretty sure the problem with my A/C is that i have leaking upper and lower hoses. Has there been a write up on replacing those? When i was shopping for replacement hoses, there are a couple of fitting options, does anyone know what type of fittings go in a 2002 3.3 v6 S/C Frontier?

 

[Cusser]

When i was shopping for replacement hoses, there are a couple of fitting options, does anyone know what type of fittings go in a 2002 3.3 v6 S/C Frontier?

Contact AMA Auto Refrigeration in Phoenix, at ackits.com. They can also repair your existing hoses, as should any dedicated auto AC shop.

My non-Frontier truck (OK, a 1988 Mazda B2200) has been running with a repaired high pressure hose for a decade now; shop welded in a new hose barb and recrimped, no more leak.

 

[hybridamp]

Very helpful write-up and great pics. Thanks for this!

 

[L8KRFAN]

I know it's old but I just wanted to say thanks for this post!

Today I went to West Covina Nissan and purchased the part ($41) and it took maybe 30 minutes to install.

I didn't have a screw driver long enough to reach the hidden screw so instead I used a 10mm socket (which is the size of the screw head) along with a swivel attachment and a long socket extension and was able to get it out that way. Also, after separating the box, I was able to reach in and use my hand to remove the old part and install the new one. I must have small hands! Lol.

AC works fantastic!! No more intermittent issues with it going on and off.

Thank you!

 

[Roader]

Thanks for this excellent DIY. I just replaced mine and found that you can get enough room to get even a big hand in to R&R the thermoamp by pulling the lower case down and hooking it under the bracket on the center console, the bracket that the lower-left glove box screw goes in to. And that gives enough room for a skinny shop vac nozzle to suck out all those dead leaves.

And now the compressor cycles normally.

 

[kevinjohnson3216]

How do you completely open the evaporator core housing to properly clean the evaporator core instead of squeezing my hand through the small crack?

 

[Roader]

I don't know. But hooking the bottom case on that bracket gives more space than a small crack. More like three inches. I had no problem getting my whole left hand in, pulling the old thermoamp out, and putting the new one in the same spot. And the thermoamp is back aways, maybe eight inches from the front of the case, so my hand was in just past my wrist.

I don't know how the evaporator is properly cleaned, but you could easily get a compressor blow nozzle in the thermoamp side and blow toward the right, vacuuming out any debris. Aside from some dried leaves at the bottom of the right side of the case, the evaporator didn't look all that dirty.

 

[kevinjohnson3216]

Where does the housing suck air from?

The last time I had my evap housing open it wast too dirty but now I'm parked under these big trees that drop tiny fingernail sized leafs by the thousands so I'm concerned it may need to be cleaned more often depending where the suction is?

 

[Roader]

Well, all the leaves were on the right (passenger) side of the duct, so that must be the intake side. The FSM pic seems to confirm that. So blowing with a compressed air blow gun on the left side would back flush any dirt/debris towards the intake. Then just vacuum up whatever gets blown out. A vacuum crevice tool would be ideal.

Now that you mention it, it would have been so easy to do while replacing the thermoamp. I may well do that before the hot weather rolls in. And maybe get a can of evaporator cleaner? Amazon sells something called Foaming Evaporator Cleaner for $10.

 

[wonka]

I just replied this in another post, but it may be more relevant here, so my apologies if you read it twice.

So I know I may not have needed to order this, but I did. According to courtesy parts, the correct one for my 2000 SE was the 27675X.

After receiving the part and taking my glove box out, I noticed that I do not have a part that looks like the replacement one I received. So I looked at the picture of the other 27723N part and mine does not match that one either. The one I have is a small black box with a circuit board inside. there are only 2 black wires running from this little black box into the condensor box unlike the 3 wires that the new part has. It does have the same female connector as the replacement part.

Now I am not sure if I needed to order this part, but now that I did, I will keep it for the future, but I am still confused why my 2000 (manufactured in 08/99) has a part that I cannot find listed on the courtesy parts list, and I am curious that if I have an issue with my thermal control amp, can I install this new one even though it looks completely different. I have attached a photo of what my part looks like.

Any thoughts?

 

[Roader]

I don't think that part will work. This one worked on my 2000XE and it's listed on that webpage to work on all models from '98 to '04.

 

[wonka]

I don't think that part will work. This one worked on my 2000XE and it's listed on that webpage to work on all models from '98 to '04.

That is the exact replacement part I ordered. Just wondering if it will work to replace my old part which is not a physical match, but has the same female connector as this new one

 

[Roader]

So the black part in your picture is your old part? And only two wires? IDK if the three-wire part will work or not. Wiring diagram for the three-wire part attached. Does the connector that the TCA plugs into have two or three wires? The wire colors on the connector on my truck are blue, blue/black, and green/orange.