[beking32]

You can use aluminum and copper together. It is common in building wiring, but you shoud use noalox, as copper and aluminum together with electricity create an electrolysis effect, that will corrode the wires at different rates. You can get it at home depot or lowes.
View attachment 206027

Ok thanks good info

 

[Z09B4U]

Also will using aluminum wiring with copper a bad thing to do?

The last time I saw aluminum wiring was on either a 76 Cutlass or maybe a 1980 Olds 98(front to back tail light harness). Where did the aluminum wiring come from?

You can not solder aluminum wiring to copper so you would have to use crimp splices that are weather proof or cover them with double wall heat shrink. You need to keep everything including air out to prevent oxidizing which will damage the connection.

It is best to avoid aluminum wiring as it is known to compress(flow) and lose connection with whatever you are trying to connect it to. It would have to be supported or you risk the flexing wire cracking and breaking.

Any chance it is marine wire which has unique stranding, the strands are much finer and each individual strand is tinned?

 

[beking32]

The last time I saw aluminum wiring was on either a 76 Cutlass or maybe a 1980 Olds 98(front to back tail light harness). Where did the aluminum wiring come from?

You can not solder aluminum wiring to copper so you would have to use crimp splices that are weather proof or cover them with double wall heat shrink.

It is best to avoid aluminum wiring as it is known to compress and loose connection with whatever you are trying to connect it to.

Any chance it is marine wire which has unique stranding, the strands are much finer and each individual strand is tinned?

Walmart wiring. I used solder seal wire connections.

 

[Z09B4U]

I edited my post please check it for the many reasons not to use aluminum wiring. It has many ways to fail in a car environment.

It was allowed then banned in house wiring in most of the world. It is used in "fixed" (no vibration) areas in places where engineering makes it beneficial.

 

[Z09B4U]

Aluminum as a Metal

Aluminum possesses certain qualities that, compared with copper, make it an undesirable material as an electrical conductor. These qualities all lead to loose connections, where fire hazards become likely. These qualities are as follows:

• higher electrical resistance. Aluminum has a high resistance to electrical current flow, which means that, given the same amperage, aluminum conductors must be of a larger diameter than would be required by copper conductors.
• less ductile. Aluminum will fatigue and break down more readily when subjected to bending and other forms of abuse than copper, which is more ductile. Fatigue will cause the wire to break down internally and will increasingly resist electrical current, leading to a buildup of excessive heat.
• galvanic corrosion. In the presence of moisture, aluminum will undergo galvanic corrosion when it comes into contact with certain dissimilar metals.
• oxidation. Exposure to oxygen in the air causes deterioration to the outer surface of the wire. This process is called oxidation. Aluminum wire is more easily oxidized than copper wire, and the compound formed by this process – aluminum oxide – is less conductive than copper oxide. As time passes, oxidation can deteriorate connections and present a fire hazard.
• greater malleability. Aluminum is soft and malleable, meaning it is highly sensitive to compression. After a screw has been over-tightened on aluminum wiring, for instance, the wire will continue to deform or “flow” even after the tightening has ceased. This deformation will create a loose connection and increase electrical resistance in that location.
• greater thermal expansion and contraction. Even more than copper, aluminum expands and contracts with changes in temperature. Over time, this process will cause connections between the wire and the device to degrade. For this reason, aluminum wires should never be inserted into the “stab,” “bayonet” or “push-in” type terminations found on the back of many light switches and outlets.

Inspecting Aluminum Wiring

This article describes the problems associated with aluminum wiring, how to identify it, and suggestions that inspectors can offer their clients.

www.nachi.org

 

[beking32]

Everyone the ac is working. Thank you everyone. All the wiring was good. Koolaid man (kiwi strawberry is the flavor) said to ground blue 55 and it worked. My pcm will need to be programmed for my ac. Until then I will use it this way. Thanks everyone. Kool aid on me. 🍻

 

[KoolAidMan]

Glad it worked out, but remember, it should be temporary till you can get the proper tune. Grounding pin 55 in a truck tune with a/c type set at “analog cycling”, tricks the pcm into thinking that the pressure switch, not sensor, is okay and can cycle the compressor. Thing is, it will never turn off and cycle, and both fans will not come on, only one. Best thing to do is definitely get a f body base tune and work from there. And for anyone who didn’t see my swap post and this thread is more suitable for this info, wiring should be as follows:

High pressure switch
Gray wire - blue - pin 45 : 5V reference

Red/black - red - pin 14 : pressure signal

Black - blue - pin 60 : low reference
(Different low ref pin can be used here. My harness happened to have this slot empty)


And the rest of the wiring, coming from stock LT1 harness and relays

A/c Request - blue wire - red -pin 17

Ac clutch enable - green - red pin 18

A/c relay - green/white - red pin 43



This is for RED/BLUE PCMs only! Also A/C type must be set to “analog”. Green/blue pcms and up require more work but can be done. Hope this helps others out too!

 

[beking32]

Glad it worked out, but remember, it should be temporary till you can get the proper tune. Grounding pin 55 in a truck tune with a/c type set at “analog cycling”, tricks the pcm into thinking that the pressure switch, not sensor, is okay and can cycle the compressor. Thing is, it will never turn off and cycle, and both fans will not come on, only one. Best thing to do is definitely get a f body base tune and work from there. And for anyone who didn’t see my swap post and this thread is more suitable for this info, wiring should be as follows:

High pressure switch
Gray wire - blue - pin 45 : 5V reference

Red/black - red - pin 14 : pressure signal

Black - blue - pin 60 : low reference
(Different low ref pin can be used here. My harness happened to have this slot empty)


And the rest of the wiring, coming from stock LT1 harness and relays

A/c Request - blue wire - red -pin 17

Ac clutch enable - green - red pin 18

A/c relay - green/white - red pin 43



This is for RED/BLUE PCMs only! Also A/C type must be set to “analog”. Green/blue pcms and up require more work but can be done. Hope this helps others out too!

What will happen if it stayed this way for awhile? Just asking? I will wait till fans kick on before turning on ac. My compressor did cycle off but the fans did not come on right away.

 

[95wagon]

just throwin this out ,
as you have found

Your #55 grounds through the low pressure switch .
The Impala that switch is on the AC request wire.

02 Camaro

02 truck

96 Impala

 

[KoolAidMan]

Pin 55 is tied to a low pressure switch so it will not be able to see when you have no Freon and will continue to run the compressor. That’s why the sensor and f body tune is the way to go. And thanks for the diagrams! Way better than the ones I have found and posted!