power window 3 prong safety relay

The power windows operate slowly, but connecting 12 volts directly to the motors allows them to function properly. A previous discussion mentioned using a common 5-pin ice cube relay, but there was no confirmation of its effectiveness. The power window relay is designed to allow operation only when the ignition key is ON, with power sourced from the AMP meter post rather than the ignition switch. According to the wiring diagram, utilizing a 4 or 5-pin ISO cube relay for controlling the power windows should be straightforward. It is advisable to select a quality relay, potentially an OEM relay without a diode, sourced from a junkyard vehicle, ensuring it has thick wires on the socket for ease of installation. A 40-amp relay is recommended, which should be mounted appropriately, as the relay coil will be energized while the ignition is ON, causing it to heat up.

The relay has a 3-prong configuration. The plug consists of three wires: a small tan wire (18 ga) connecting to the AM 8-track and then to the main harness, a large red wire (12 ga) leading to the back of the amp meter and a 30-amp circuit breaker, and a large tan wire (12 ga) going to the main window switch. This relay resembles a key buzzer relay with a similar 3-prong connection and is grounded through its mounting tab to the dash. The wiring configuration includes a top connector for the red wire and two bottom connectors for the tan wires. The relay coil generates a magnetic field when powered by the ignition switch, with one end grounded to the relay case, which prevents removal. While a conventional horn relay might work, it is not recommended due to differences in winding that could lead to overheating under continuous current.

To ensure reliable operation, it may be necessary to depin the connector body and connect directly to a 4 or 5-pin relay, running an additional wire from either pin 85 or 86 to ground to complete the control circuit. If the terminals can be detached from the connector body, they can be plugged directly into a relay socket or the relay itself without cutting any wires. If not using a relay socket, applying shrink tubing around the various wires is advisable. The relay functions as a single-pole single-throw (SPST) relay, with one side of the coil grounded to the metal case, disabling window power when the ignition switch is OFF. The slow operation of the windows is attributed to the window switches, which ground through the driver’s switch. Installing a motor reversing relay (comprising two double-pole single-throw relays) between each switch and window motor can enhance window speed and alleviate the high current load on the factory switches.

The relay previously discussed is a 3-prong type that requires mounting to the dash for proper grounding. The relay configuration appears compatible with the wiring diagrams available, although the small tan wire to the 8-track is not present in all schematics. Typically, the factory setup involves mounting the relay to the dash and connecting the 3-way connector directly to it, ensuring a reliable and efficient power window operation.Works but the windows go slow, you hook 12 volts directly to the motors and they zip up fine. I saw a post from several years ago where someone was trying to use the common 5 pin ice cube relay. never saw anything that said it worked. Anybody know the power window relay allows the power windows to be operated only when the key is ON. and the power for the windows comes from the AMP meter post. NOT the ignition switch. in looking at the wiring diagram. is should be very easy to use a 4 or 5 pin ISO cube relay to control your power windows. you might want to find a quality brand. either grab an OEM relay without diode shown in the diagram on the side from a junk yard car. with thick wires on the socket. this will make your life easier. you may want a 40 amp relay. and you will want to position it. and mount it somehow. as this relay is going to have the coil wired as long as you have the key on. so its going to get warm. It`s a 3 prong relay. The plug has 3 wires that the relay plugs into. small(18 ga) tan wire goes to the am 8 track and then to the main harness, the big red wire (12 ga) goes to the back of the amp meter and 30 amp circuit breaker. and the big tan wire (12 ga) goes to the main window switch. The relay looks like a key buzzer relay with the same 3 prong connection. It`s internally grounded by the mounting tab to the dash. So I am dealing with 3 wires and a possible external ground. Imagine a 3 prong connecter one plug on top and 2 below. Looking at the plug as if you were going to plug the relay in the red wire is on top the small tan wire is to the bottom left the big tan wire is on the bottom right.

knowing this info do you think your pin config will work the relay shown above HAS the coil that creates the magnetic field when power is applied from the ignition switch. one end of the coil is grounded to the case of the relay. preventing you from removing it. you might get by with a convention horn relay. but they are wound differently and may burn up when exposed to the long term current through the coil.

this is a constant duty relay. now. you might want to Depin the connector body. and connect directly to the 4 or 5 pin relay. you will need to run a 4th wire from either pin 85 or 86. to the ground. so you have a complete control circuit. and in doing this. if you can unlatch the terminals from the connector body. you can plug them directly into a relay socket. or directly to the relay. without cutting any wires. i would if NOT using a relay socket. use some shrink tubing carefully applied around the various wires. There is nothing special about the relay. It is just a SPST relay, but I think one side of the relay coil is grounded to the metal case. It just disables the window power when the ignition switch is OFF. The windows being slow is because of the window switches, and they all ground through the drivers switch. Adding a motor reversing relay (basically two DPST Relays) between each switch and window motor will make the windows operate faster, and take the high current load off of the factory switches.

I had explained the relay fix prior to this, but this thread seems easier to find when I searched for it: it was 3 prong as you show and I realize that it needed to be mounted to the dash to create the grounding. I am sure the relay you show would work. So I guess you would mount it, then plug the 3 way connector to the relay. I am sure that was part of the "safety" factor. Is that relay easier to find I was able to look at your diagram as well as the diagram in my Factory service manual and the wiring was close.

I just didn`t see the small tan wire that went to the 8 track on yours. So I am sure from the factory they mounted the relay to the dash and plugged the 3way connecter in. Th 🔗 External reference