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how to wire a relay

  
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how to wire a relay

 
joshcanfield joshcanfield
I love my Chevy Chevette! | Posts: 24 | Joined: 02/13
Posted: 03/13/13
01:22 PM

I am installing a new relay in my elcamino for the air conditioning unit.
I bought a new relay and a a wiring connector. the old relay and wires are too messed up to use them as a guide can any one tell me how to install the relay

Imag0208fl
New

Imag0209lz
Original

Imag0210z
wiring diagram from chevy shop manual.  

68scott385 68scott385
I have an SS396 tatoo | Posts: 325 | Joined: 07/09
Posted: 03/13/13
02:57 PM

The new one is a direct replacement for the old one, right? Remove one install other. The wires fromn the new connector go to the wire in the same location as the old one. Left wire to color X. Left center wire to  color XY. Rinse & repeat as needed.  
68scott385 68scott385 68scott385

waynep71222 waynep71222
My first time was in a Chevy | Posts: 218 | Joined: 04/12
Posted: 03/13/13
08:28 PM

follow instructions above... figure out which wire went where.. crimp new pigtail in one wire at a time.. verify ...  go to next wire...

for others...  the terminals come out rather easily on these pigtails.. you can note the location as not all use 5 wires..   remove the terminals from the connector body.. and slip some shrink tubing over the terminal and shrunk insulation..  then heat the shrink tube and reinstall the terminal.. this saves the cutting and splicing..


here is the wiring schematic for the relay

you will have to identify which terminals are marked 1 thru 5 on your part...


GM Relay 5 Pin Inline Zps309ef057


i cannot identify the wire colors on the harness connector you cut out..

the manual diagram looks like a different relay.. than what i cross referenced off the part number...

if shows mostly 81 to 84 gm cars.. montecarlo.. ..

i will have to go back and look at your other posts to see what you are working on unless you can post the year and which motor elcamino...

i have an amazing amount of info stashed here and there..






WARNING WARNING WARNING... that is MIGHT BE A  DIODE protected relay.. between pins 1 and 2... if you hook it up backwards.. you will blow the diode out and ruin your relay...  

that diode is in there to prevent a HIGH VOLTAGE spike when the ECM releases the ground connection to the coil winding..



by the way.. there are like 4 sections of wiring harness under your hood..

harness to the headlights, turn signals and horn... sometimes a few other parts..

harness to the engine...   HEI, alternator, choke thermostat.. oil pressure switch.. temp switch.

HVAC harness... this usually comes through the firewall to connect to the compressor . blower motor,  various ac pressure switches..

then the removable  FEEDBACK harness...  that comes thru the firewall..  

waynep71222 waynep71222
My first time was in a Chevy | Posts: 218 | Joined: 04/12
Posted: 03/13/13
09:11 PM

additional... i have a 4 page wiring diagram for the 82 elcamino...  if you are working on something else.. please mention this..

colors

RED is POSITIVE  directly from one of the 2 fusible links at the top of the starter solenoid.

Orange is from the HIGH position of the blower switch in the dashboard.,

black goes to ground...

Dark BLUE.. goes to the blower resistor..

Purple goes to the terminal on the heater blower..

the wiring diagram shows the relay wired slightly different for cars without AC...  

joshcanfield joshcanfield
I love my Chevy Chevette! | Posts: 24 | Joined: 02/13
Posted: 03/15/13
08:03 PM

ok, thank you waynep71222 this has been the most promising info I have recieved so far. A little more about my car. It is a 1982 el camino and had ac when I purchased it. The original engine was a  229 and had a cracked block, so I had a 350 pulled from a '73 pickup. I dont know what model pickup was though. I didn't have the tools to pull the engine my self at the time. the a/c didn't work and the relay was not connected to anything so I can't trace any of the wires back to their original connection. as best I can tell from the colors going from left to right of my photo is green, brown, brown, brown, green w/yellow stripe. from left to right the wires are installed in each slot double green, blank, brown, double brown, double green/ yellow stripe. there doesn't seem to be black wire at all. all of my other wiring I have, via the Diagram, is correctly wired. the diagram I have is the 1982 chevrolet shop manual electrical supplement.  

joshcanfield joshcanfield
I love my Chevy Chevette! | Posts: 24 | Joined: 02/13
Posted: 03/15/13
08:33 PM

Here is a Picture of the condenser side of the AC unit

20130315220754

I pulled the "jacked up" wiring harness for the emc down and to the side.  

waynep71222 waynep71222
My first time was in a Chevy | Posts: 218 | Joined: 04/12
Posted: 03/15/13
09:26 PM

repost that image at image shack..  whats there is so small. and at such a low resolution that i cannot blow it up to see whats there.. could have been the camera setting also.

be sure to NOT resize the image.. or reduce.. it..

this is going to be a hard one ...

get in closer and post several images.. they are free to post..

i will look at your wire colors sat morning..  

68scott385 68scott385
I have an SS396 tatoo | Posts: 325 | Joined: 07/09
Posted: 03/16/13
07:47 AM

In my experiences with Chevy wiring and the color codes in the manuals is that the wires are not always the color the manual says they should be. This has ahppened on more than one occasion with more than one car.

Good Luck Josh!  
68scott385 68scott385 68scott385

waynep71222 waynep71222
My first time was in a Chevy | Posts: 218 | Joined: 04/12
Posted: 03/16/13
08:26 AM

as best I can tell from the colors going from left to right of my photo is green, brown, brown, brown, green w/yellow stripe. from left to right the wires are installed in each slot


double green,

blank,

brown,

double brown,

double green/ yellow stripe.


hmm.... my mitchell wiring diagram for the 82 chevy application G bodies.. is 4 pages long..

it does not show a relay with those colors.. does not mean it does not exist..

since you have a factory service manual.. does it cover the G bodies.??

page thru the wiring diagrams.. do you see a relay with those colors..


back at the car... DOES the heater fan work on all three speeds??? currently.. with this relay disconnected???

the purple wire from the blower motor.. will probably run into a relay.. or into the resistor block in the blower housing..


this is the blower motor resistor.


this is the connector.. wire colors may not match..




this is whats shown for the high speed low speed blower motor relay.


and the connector shown for this relay...

 

joshcanfield joshcanfield
I love my Chevy Chevette! | Posts: 24 | Joined: 02/13
Posted: 03/16/13
11:43 AM

Blower dose not work in any speed. It is a new blower though the old one was missing. Also I can not find this coloring any where for the relay, on any pictures.

here are some more images

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Blower Motor Resistor

Imag0216m
High Speed Blower Motor Relay

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Pressure Cycling Switch on condenser

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wiring from firewall

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A/C compressor clutch

Imag0222ty
full page on "G" series. this is the only diagram in the book

Imag0224x
here is what I believe it is narrowed down to since originally I had the LC3 engine  

waynep71222 waynep71222
My first time was in a Chevy | Posts: 218 | Joined: 04/12
Posted: 03/16/13
05:34 PM

when you turn on the KEY... does the BROWN wire into the resistor connector have power.. yes or no...  yes would be GOOD.

on the relay with the various colored wires on it..

does the RED wire have constant power..?? yes or no. yes would be good

when the key is on... and the dash board blower switch is set to HIGH.. does the orange wire have power on it???? yes or no... yes would be good.

82 Chevy G Body Blower Resistor Zpsc0531feb


when you connect direct power to the blower  motor where the purple wire was connected.. does the blower motor spin??? yes or no...  yes is good.. if no .. check ground connection on the blower motor mounting face to ground...

now.. back to the relay.. with the purple and orange wires on it..   when you turn the fan switch to HIGH.. then turn the key on.. does that relay CLICK??? yes or no..   if yes.. good.. and the fan should be spinning at high speed... if no.. check the ground connection on one of the wires. location on the relay to come..  as that is the relay i posted.. with a different bracket.. that does not have the connector inline...  

waynep71222 waynep71222
My first time was in a Chevy | Posts: 218 | Joined: 04/12
Posted: 03/16/13
05:50 PM

now on the compressor control side of the circuit...

Imag0218xc

see the light green wires...  one of those comes from the ac control switch. the other went to the ECM or to the ac idle solenoid..  think of an idle stop solenoid..  the dark green wire goes to the compressor clutch...

you can actually unplug this from the pressure switch and use a short jumper wire made with .250" male quick connects to force the compressor clutch to engage for testing..

Imag0221kl

please cut out that horrible looking tape job on the green wire over the cruise control .. make sure its a CRIMPED blue connector...  

the black wire thats connected to the mounting ear on the ac compressor also needs a blue ring terminal not a yellow one.. and please be sure that the ring terminal is contacting ground.. not paint... paint is not going to cut it..

if you run power directly to the green wire.. you should be able to make the clutch pull in.. even with the engine off...    warning.. there is a DIODE in that ac compressor connector..  if that diode blows out.. for some reason the compressor clutch will not engage..  

joshcanfield joshcanfield
I love my Chevy Chevette! | Posts: 24 | Joined: 02/13
Posted: 03/16/13
08:15 PM

...well...I feel like a total bumb A**, I had a blown fuse. I don't know when it happened, I could have sworn that I checked the fuses several times. My fan blows great on all speeds. I still checked like you said waynep71222. Everything checks out fine. the only thing is the relay is the only thing connecting the A/C compressor clutch and the pressure cycling switch. the WOT relay is controlled by the computer am I correct? I know that Waynep71222 was also poasting on another thread about me cleaning up some of the wiring in the engine bay. If I removed the computer would the relay be usless? would I bypass it or is there another solution?  

waynep71222 waynep71222
My first time was in a Chevy | Posts: 218 | Joined: 04/12
Posted: 03/16/13
08:33 PM

i described how to wire it without a computer...

light green wire from the back of the control panel to the pressure switch.. dark green to the compressor clutch..

with the V6 under computer control..  it needed to disconnect the AC Compressor sometimes..

you will also want to cut into the compressor drive circuit under the dash and put a good toggle switch thats labeled.. or a push and hold button  like japanese cars did.. so the compressor does not run all the time you have anything other than OFF selected...

the brown wire feeding the resistor is the positive ventilation circuit.. it turns on the blower motor at about half the speed of LOW on the fan switch..  this is to keep exhaust fumes out of the car.. by having the blower running at low speed when the key is on...  

joshcanfield joshcanfield
I love my Chevy Chevette! | Posts: 24 | Joined: 02/13
Posted: 03/16/13
08:56 PM

Sorry, Yes I see it now, I didn't refresh my page so I didn't see that last part...
I will do what you said about cleaning up that wiring attached to the compressor side, as well as the work on bypassing the computer. I will post the changes when I am done with them.  

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