Nissan d21...Need to know which wire on the relay does the compressor connect to. I tested each comes out different output, 0, 0.5, 11.2 and 12.5.

Question edited for typos.

These are the D21 wiring details. The best way is to get a conversion harness D21 to JVS from Crutchfield.

1994 Nissan Hardbody Pickup Stereo Wiring - The12Volt

https://www.the12volt.com > installbay > stereodetail
1994 Nissan Hardbody Pickup car stereo wire colors, functions, and locations.

Nissan Hardbody radio wiring colors

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Mar 5, 2011 - have rear wires i ran my own but this was schematic for after market plug to harness so colors should be right unless back are missing and ..

Do you know how to test relay circuit's ? Voltage , control etc...

DTC P1545
Circuit Description
Ignition voltage is supplied directly to the A/C compressor clutch relay. The powertrain control module (PCM) controls the relay by grounding the control circuit through an internal solid state device called a driver. The primary function of the driver is to supply the ground for the component being controlled. Each driver has a fault line which is monitored by the PCM. When the PCM is commanding a component ON, the voltage of the control circuit should be near 0 volts. When the PCM commands the control circuit to a component OFF, the voltage potential of the circuit should be near the battery voltage. If the fault detection circuit senses an unexpected voltage, this DTC will set.
Conditions for Running the DTC
• The engine is running.
• System voltage is between 8-16 volts.
• The PCM driver is activated.
Conditions for Setting the DTC
• The PCM detects an incorrect voltage level on the output circuit that controls the A/C compressor clutch relay.
• The condition exists for at least 10 seconds.
Action Taken When the DTC Sets
• The PCM will not illuminate the Malfunction Indicator Lamp (MIL).
• The PCM stores the failure records.
• The A/C compressor clutch is disabled.
Conditions for Clearing the DTC
• The DTC will clear after 50 fault-free ignition cycles.
• The DTC can be cleared with a scan tool.
Diagnostic Aids
If the condition is not present, refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
Listen for an audible click when the A/C compressor clutch relay operates. Command both the ON and OFF states. Repeat the commands as necessary.
Tests for voltage at the switch side of the A/C compressor clutch relay. The 10-amp fuse supplies power to the switch side of the A/C compressor clutch relay.
Verifies that the powertrain control module is providing ground to the A/C compressor clutch relay.
Tests if ground is constantly being applied to the A/C compressor clutch relay.
Tests for a short to voltage or for an open.
Perform the calibration procedure for the powertrain control module.
Step
Action
Yes
No
Schematic Reference: HVAC Schematics
1
Did you perform the HVAC Diagnostic System Check?
Go to Step 2
Go to Diagnostic System Check - HVAC Systems - Automatic
2
Install a scan tool.
Turn ON the ignition, with the engine OFF.
With a scan tool, command the A/C Relay ON and OFF in the Engine Output Controls list.
Does the A/C Relay turn ON and OFF with each command?
Go to Diagnostic Aids
Go to Step 3
3
Turn OFF the ignition.
Disconnect the A/C compressor clutch relay.
Turn ON the ignition, with the engine OFF.
Probe the battery positive voltage circuit of the A/C compressor clutch relay with a test lamp.
Does the test lamp illuminate?
Go to Step 4
Go to Step 10
4
Connect a test lamp between the control circuit and the battery positive voltage circuit of the A/C compressor clutch relay.
With a scan tool, command the A/C Relay ON and OFF .
Does the test lamp turn ON and OFF with each command?
Go to Step 8
Go to Step 5
5
Does the test lamp remain illuminated with each command?
Go to Step 7
Go to Step 6
6
Test the control circuit of the A/C compressor clutch relay for a short to voltage or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 13
Go to Step 9
7
Test the control circuit of the A/C compressor clutch relay for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 13
Go to Step 9
8
Inspect for poor connections at the A/C compressor clutch relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 13
Go to Step 11
9
Inspect for poor connections at the harness connector of the powertrain control module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 13
Go to Step 12
10
Repair the battery positive voltage circuit of the A/C compressor clutch relay. Refer to Wiring Repairs in Wiring Systems.
Did you complete the repair?
Go to Step 13
--
11
Replace the A/C compressor clutch relay. Refer to Compressor Relay Replacement in Heating, Ventilation, and Air Conditioning.
Did you complete the replacement?
Go to Step 13
--
12
Important: Program the powertrain control module .
Replace the powertrain control module. Refer to Powertrain Control Module Replacement in Engine Controls.
Did you complete the replacement?
Go to Step 13
--
13
Use the scan tool in order to clear the DTCs .
Operate the vehicle within the Conditions for Running in the DTC, as specified in the supporting text.
Does the DTC set again?
Go to Step 2
System OK

Get the alternator tested. It might not be working at full output. Also test the battery it may need replacing.

DTC C0655
Level Control Compressor Relay Malfunction .
You start by doing the diagnostic tests for that code .
Circuit Description
The automatic level control adjusts the vehicle suspension ride height. The RIM determines the height of the vehicle based on the voltage from the automatic level control sensor. The RIM grounds the compressor relay and the exhaust control solenoid to raise and lower the vehicle in order to keep the vehicle level.

Diagnostic Aids
• Inspect all wiring harnesses carefully for chaffs and proper routing. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
• This circuit is monitored before every functional operation of the compressor relay output. If a compressor relay fault is detected, the RIM retries the output every 15 seconds to try to recover from the fault.

Your probably not going to be able to do the factory diagnostics unless you have a factory scan tool to turn on an off the relay . You can test with a volt meter at the relay for B+ voltage and control from the RIM - Rear Integration Body Control Module. Do you know what a relay is and how it works ?

2
Install a scan tool.
Turn ON the ignition, with the engine OFF.
With a scan tool, command the level control compressor relay ON and OFF.
Does the level control compressor relay turn ON and OFF with each command?
--
YES Go to Diagnostic Aids
NO Go to Step 3
3
Turn OFF the ignition.
Disconnect the level control compressor relay .
Turn ON the ignition, with the engine OFF.
Probe the coil side feed circuit of the level control compressor relay with a test lamp that is connected to a good ground.
Does the test lamp illuminate?
--
YES Go to Step 4
NO Go to Step 10
4
Connect a test lamp between the control circuit of the level control relay and the coil side feed circuit of the level control compressor relay.
With a scan tool, command the level control compressor relay ON and OFF .
Does the test lamp turn ON and OFF with each command?
--
YES Go to Step 8
NO Go to Step 5
5
Does the test lamp remain illuminated with each command?
--
YES Go to Step 7
NO Go to Step 6
6
Test the control circuit of the level control compressor relay for a short to voltage or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
--
YES Go to Step 13
NO Go to Step 9
7
Test the control circuit of the level control compressor relay for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
--
YES Go to Step 13
NO Go to Step 9
8
Inspect for poor connections at the level control compressor relay . Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
--
YES Go to Step 13
NO Go to Step 11
9
Inspect for poor connections at the harness connector of the RIM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
--
YES Go to Step 13
NO Go to Step 12

10
Repair the coil side feed circuit of the level control compressor relay . Refer to Wiring Repairs in Wiring Systems.
Did you complete the repair?
--
YES Go to Step 13
--
11
Replace the level control compressor relay.
Did you complete the replacement?
--
YES Go to Step 13
--
12
Replace the RIM. Refer to Rear Integration Body Control Module Replacement in Body Control System.
Did you complete the replacement?
--
YES Go to Step 13
--
13
Use the scan tool in order to clear the DTCs .
Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.
Does the DTC reset?
--
Go to Step 2
System OK

Visit the on-line store, know as reliable-store, they have the repair manuals. I'm sure you will get the solution of your problem.
NISSAN D21

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Nissan Hardbody Pickup Truck Factory Service Manuals

www.nicoclub.com/.../nissan-hardbody-pickup-truck-factory-service-ma...

Jan 1, 2000 - The Nissan D21 series pickup trucks, also known as the NissanHardbody, were ... Please select your year to access the Factory Service Manual: ...1991 - coming soon... 1992 - coming soon... 1993 - coming soon... 1994

In the fuse box,test circuit with a test light.

sold all over earth, what country> we cant guess this....
don't break the brakes....!!!
my guess, you meant the
brake lamps are on keys in pocket. and the battery lamp is dash(charge) glows, keys in pocket. right?
and battery cable kills all this illegal states above. sure.

86 nissan PU.
720 PU>? Datsun>?
or D21 Nissan ( 1986 Dat-SUNS became NISSANS. in USA)
Model years 1986.5 (second half) and later were called Nissan Hardbody Trucks, chassis code D21.

D21 are called HARD BODY trucks. mid year changes.
so???? which is yours.

as you might not ,know , the models are wired diffrent by different exact models and country.
long ago , i had the 86 with the VG30 V6...

so i will roll the dice and answer for
D21
ok?

things off stay on, 101
bad wiring, hacked in wiring, radios,alarms and other things.
all can cause this..... its old and is common on old cars.
but if wiring is not hacked, (id see that in 10seconds in person)
no hacks.
gas engine car not diesel.
USA 86 body
brakes
Im looking now at the schematic and this car has a hot at all times
brake lamp switch. (foot pedal switch)
SO only a bad switch can cause this.... period
now the dash charge (battery ) light stuck on.


my online source ,has the alternator system missing.
so can not comment.
the lamp gets its power from the key switch
if the key switch fails , all warning lanps glow not just the
charge.(battery)
so its not that
my best guess is wiring errors, that put power the the cluster
key off. id bet that is it .

wiring errors to the ignition output is side, key switched power is failing.

I know you stated you checked all fuses and relay and they're ok but The 2003 Lincoln Navigator had two differently (wired) air ride systems. A early production and a late one, and I think I may have a good Idea of what your problem may be and will walk you through how to properly test the system. The early production navigators used a solid state compressor relay and the later production units used a standard style relay. The early ones with the solid state type has been known to have some problems and working for a Ford, Lincoln Dealer for 21 years I have replaced a good number of these solid state relay for a air ride compressor inoperative concern. There seems to be some confusion on the location of the solid state relay. I would advise you to look behind your front bumper on the passengers side of your vehicle (and below your headlight) and see if you have a 4 wire relay that's aluminum and finnd ribs on the front of it and I believe a black base where the wiring connector plugs in. (this will be mounted to the radiator support) if so, you Have got the early production style. I will walk you through how to test this relay and also help you to isolate the cause of your problem. I highly recommend using a volt ohm meter for these tests. I do not recommend using A TEST LIGHT due to the fact that you will be testing a circuit that is wired to the air ride control module, and there is a possibility of you damaging the module with a test light !!! I have been there, done that, NOT GOOD.
Ok with that said: your wire colors should be as follows:
one that's( gray and red)
another that's (light green and red)
another that's (dark blue and yellow)
and one that (light blue and pink).
Disconnect the connector at the relay and you'll be testing the wires in the connector (THAT HOOK UP TO THE RELAY). The air ride compressor and the air ride solid state relay share the same ground which is the light green and red wire.
Turn your volt ohm meter to dc volts scale and attach the black wire (NEGATIVE) lead of the volt ohm meter to the light green and red wire.
Hook the red lead of the volt ohm meter to the light blue and pink wire.
Here your volt meter should read battery voltage (of your car's battery) if not check the (F2-111) 50 amp designated fuse in the fuse box under the the dash on the passengers side (KICK PANEL).
If this fuse is ok, make sure you were making good contact with your test leads into the compressor relay connector.
If you're comfortable with the fact that you have a good connection at the relay connector and your fuse tested ok, then you have a ground problem at ground point G101 which is located right near the mounting location of the air ride relay.
If you had battery voltage when you tested between the (light green and red) and the light blue and pink wires, you have confirmed the power source and ground to the relay.
I should clarify myself at this point. The wires at the relay are as such: The ground is the light green and red wire, the light blue and pink is the fused power source to the relay, the dark blue and yellow wire is the relay trigger source from the air ride module to the air ride relay, and the grey and red is the relay output (battery +) to turn on the compressor. OK.
So now we're down to checking the trigger source to the relay and the relay output. At this point I want you to re-hook up the volt ohm meter with the meter still set at volts d/c scale and reconnect the (red lead) of the volt ohm meter to the (light blue and pink wire) and connect the (black) lead of the volt ohm meter to the dark blue and yellow wire (again at the relay connector).
Now this next step is best done with the help of an assistant!!
While watching your volt ohm meter, have your assistant turn on the key and open and close the drivers door two -to- three times. After cycling the door, you for a short time should see at least 5 volts minimum, if not battery voltage at your meter.
(this is a little bit unclear to me due to the fact the air ride module shows that the dark blue and yellow wire, as a ground from the air ride module to the relay. but does not clarify exactly what value that ground signal should be). I am referencing Fords own wiring diagram.
A solid state relay usally is allowed a trigger source of a lower voltage then a standard relay. If you find you have no voltage reading at your volt ohm on this test, you'll first want to check fuses F2-20 which is a 30 amp fuse and F2-27 which is a 5 amp fuse in the same fuse box as the F2-111 fuse you checked earlier.
The last test you need to make at the relay is checking the relay output to the compressor. This will be done by again using the volt ohm meter. This time you'll want to hook the black lead of the volt ohm meter to the light green and red wire at the reay connector and hook the red lead of the volt ohm meter to the grey and red wire at the relay connector. Again for this test, you'll need to have a assistant turn on the key, then recycle the drivers door again.
If the relay is working properly you should have battery voltage, aproximately 12 volts showing on your meter. If not and all other test procedures results were correct, you have a bad relay.
If you have 12 volts on this test we have confirmed the relay is good and the trigger signal from the air ride module is operating as designed.
If the pump runs like you said (when it is straight wired ) the remaining possiblity is a broke wire between the air ride relay to the air ride pump (this being the grey and red wire) which you can test by switching the volt ohm meter to the ohms scale and touching one lead of the meter to the grey and red wire at the relay connector and the other to the grey and red wire at the compressor (with the compressor and the relay both disconnected). Your reading here should be 0.5 ohms or less. If you have under 1.0 ohms you're ok but specs are 0. 5 or less.
If you have an auto ranging type ohm meter, be sure your reading in ohms and not kilo ohms or mega ohms.
If you find while performing the test from the air ride module to the air ride relay (dark blue and yellow wire) referenced as the trigger signal, incorrect and all fuses all checked o.k. then it is possible the air ride control module is defective. But, before condemning the module, there are a multitude of input signal;s to the module that would have to be checked.
WARNING: Make sure your tests are accurate. Good to check and re-check each test. Be confident of your results.
Inaccurate tests and inaccurate test results= unnecessary parts replacement. Results are large dollars spent when unneeded.
Hope this helps you out.thanks for using fixya

HI,
Yeah have the voltage to the compressor checked!..By turning on the A/C when hot (and not working),Add a test wire to the 12v output of the A/C relay, to "boost" the 12v amps/voltage going to the compressor clutch. As soon as the test wire touches a strong 12v source, the clutch immediately kicks in. Remember that 12v already existed on that wire, but a stronger 12v source helped give the clutch the extra kick it needs. Thank you!!..Hope this helps you out buddy!!.. :)