LS Swap Main Relay wiring problems
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Joined: Mar 2020
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From: PNW
LS Swap Main Relay wiring problems Hey guys so I have a 5.3 inb my 1995 montero that I am wiring up, I wired the fuse box and I tested to see if the relays would switch the PCM and the other ignition fuses on. this is how I have my ignition relay wired up:
Pin 30: Goes to the fuse buss to turn them on with ignition. Should be what the relay turns on
Pin 86: My trigger wire from the Montero that sends ignition power to the relay when the key is turned
Pin 87: 12v power straight to the battery
Pin 85: ground
So, my 12v gets power, my ground is grounded to the engine and body, my keyed ignition gets 11volts when turned . The ignition wire from the montero gets 11 volts when there is no relay in it. When I put the relay in, it goes to 0.16 volts so the relay basically just passes my keyed 12v from the montero and grounds it out. I am fairly certain that my relay is wired wrong, I just dont want to mess it up and short something out. Yes I tried other relays and had the same result. LT1 swap doesnt give the actual pins of his relay and where they go. I am not using the same style fuse box as him.
Thanks guys.
Pin 30: Goes to the fuse buss to turn them on with ignition. Should be what the relay turns on
Pin 86: My trigger wire from the Montero that sends ignition power to the relay when the key is turned
Pin 87: 12v power straight to the battery
Pin 85: ground
So, my 12v gets power, my ground is grounded to the engine and body, my keyed ignition gets 11volts when turned . The ignition wire from the montero gets 11 volts when there is no relay in it. When I put the relay in, it goes to 0.16 volts so the relay basically just passes my keyed 12v from the montero and grounds it out. I am fairly certain that my relay is wired wrong, I just dont want to mess it up and short something out. Yes I tried other relays and had the same result. LT1 swap doesnt give the actual pins of his relay and where they go. I am not using the same style fuse box as him.
Thanks guys.
Thread Starter
Teching In
Joined: Mar 2020
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From: PNW
TECH Regular
Joined: Dec 2011
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Technically you have your battery wire backwards. Terminal 30 should go straight to the battery. 87 and 87A are outputs. Are you sure that you are using 87 and not 87A?
You should be able to hear the relay click without connecting any of the battery connections. If 85 is ground and you apply 12v to 86, it should click on. If that's not happening, you have the wrong terminals.
You should be able to hear the relay click without connecting any of the battery connections. If 85 is ground and you apply 12v to 86, it should click on. If that's not happening, you have the wrong terminals.
Thread Starter
Teching In
Joined: Mar 2020
Posts: 21
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From: PNW
Technically you have your battery wire backwards. Terminal 30 should go straight to the battery. 87 and 87A are outputs. Are you sure that you are using 87 and not 87A?
You should be able to hear the relay click without connecting any of the battery connections. If 85 is ground and you apply 12v to 86, it should click on. If that's not happening, you have the wrong terminals.
You should be able to hear the relay click without connecting any of the battery connections. If 85 is ground and you apply 12v to 86, it should click on. If that's not happening, you have the wrong terminals.
Thread Starter
Teching In
Joined: Mar 2020
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From: PNW
Alright guys so apparently 11 volts is not enough to trigger this 12 volt relay. From what I have read as little as 8 volts should trigger the relay. For some reason, the wire i used to trigger the relay gets 11 volts in accessory power and on position, but then gets the full 12.5 volts in crank so that how I was able to see that it works. Thank you guys for your suggestions, it looks like i am just going to have to find another wire to trigger the relay. Or buy a better relay that is able to operate on 11 volts
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Here is what you can try:
Unplug all of the terminals, except leave 85 to ground. Now, take the wire you have to battery and touch that wire to the 86 terminal. Does it click now?
Here's the thing: Its not voltage, per se, that activates the relay, its current. The fact that your "ignition" wire to pin 86 is dropping to almost 0 volts indicates it might be something else, with a lot of resistance in line some where.
If you get a proper relay click when you jump battery directly to the 86 terminal, then you need a better ignition wire.
Unplug all of the terminals, except leave 85 to ground. Now, take the wire you have to battery and touch that wire to the 86 terminal. Does it click now?
Here's the thing: Its not voltage, per se, that activates the relay, its current. The fact that your "ignition" wire to pin 86 is dropping to almost 0 volts indicates it might be something else, with a lot of resistance in line some where.
If you get a proper relay click when you jump battery directly to the 86 terminal, then you need a better ignition wire.
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Thread Starter
Teching In
Joined: Mar 2020
Posts: 21
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From: PNW
Here is what you can try:
Unplug all of the terminals, except leave 85 to ground. Now, take the wire you have to battery and touch that wire to the 86 terminal. Does it click now?
Here's the thing: Its not voltage, per se, that activates the relay, its current. The fact that your "ignition" wire to pin 86 is dropping to almost 0 volts indicates it might be something else, with a lot of resistance in line some where.
If you get a proper relay click when you jump battery directly to the 86 terminal, then you need a better ignition wire.
Unplug all of the terminals, except leave 85 to ground. Now, take the wire you have to battery and touch that wire to the 86 terminal. Does it click now?
Here's the thing: Its not voltage, per se, that activates the relay, its current. The fact that your "ignition" wire to pin 86 is dropping to almost 0 volts indicates it might be something else, with a lot of resistance in line some where.
If you get a proper relay click when you jump battery directly to the 86 terminal, then you need a better ignition wire.
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