No crank, no start, but lights work

Hi,

A relay is basically just a fancy switch that utilizes an electrical trigger signal to activate. Once activated the relay connects an electrical supply to a particular accessory. In this case, the starter motor.

Before anything, see if it will start in neutral to eliminate a faulty park/neutral safety switch.

Here is how it works. By applying power to pin 87, you bypassed a few of the circuits and sent power directly to the start solenoid causing it to engage. The idea that it worked tells me two things. First, there is nothing wrong with the starter, and secondly, the battery is at least okay.

Here is how it works: If you look at pic 1 below, I highlighted a few things including pin 87. If you notice pins 30 and 87 are the switch portion of the relay. Pin 30 has power at all times and pin 87 only gets power when the relay is triggered.

For the relay to trigger, first the key has to be turned to the start position. At that point, power goes through a 10-amp crank fuse, then to the neutral park switch, and then makes its way to pin 86 on the relay. Once power reaches 86, it has a direct path to ground via pin 85 which completes the primary side of the relay circuit.

Once the primary side is complete, an electromagnetic field is created in the relay and pulls the switch between pins 30 and 87 closed, and power is sent to the starter solenoid to engage the starter. By jumping power from the battery to pin 87, you bypassed all of the things I mentioned. If you look through this link, it gives a better description of how the relay works and how to test one:

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

So, if you look at pics 2 and 3, I included the schematic for the starter circuit. The first things I would check are the fuses. In the under-hood fuse box is the ignition fuse (fuse 6, 40 amp). In addition to checking the fuse, confirm there is power to it. Here is a link that explains how that is done:

https://www.2carpros.com/articles/how-to-check-a-car-fuse

If that fuse is good, check fuse 8 in the fuse panel under the dash. Do the same thing. Confirm there is power to it.

If both are good, then we need to confirm two things. First, does the power make it to relay pins 30 and 86? Note: that both pins 86 and the fuse (10 amp in the vehicle) will only have power when the key is in the start position. If there is power, then you need to confirm there is a ground path via pin 85 in the relay box.

Try this and let me know what you find. I hope I made this understandable.

Pics 2 and 3 are the wiring schematic for your review. Pics 4 and 5 are the fuses I need you to check.

Take care,

Joe

See pics below.

Hi,

You are correct about the battery. If it started when you jumped the relay, then the battery is good enough to start the car.

Let me know what you find or if you have other questions.

Take care,

Joe