Ken99
New member
I have a 1999 C3500 7.4 and I'm having a hard time starting my truck. I turn the key and it just cranks. The fuel pump doesn't kick in. The headlights don't automatically come on. Other than the cranking, it seems nothing is going on under the hood.
The under the hood fuses that are 10A ENG-E, 20A ECM-I and 20 A ENG-I are not getting power when the key is in the ON position. All of the other fuses have constant power. The fuel pump relay is getting constant power on pin 87 and not getting the "two second" power on pin 85 when the key is turned on. The pump does come on if I bypass the relay. The headlights are not automatically coming on when the key is in the ON position either. They do come on if I use the switch manually.
Using a test light, I had it stuck in the larger pink wire coming out of the fuse box. I accidentally touched the power post on the side of the fuse box and everything came on until I removed the test light from the power post. The key was in the ON position.
Does anybody have any idea what the problem might be? Is it the ignition switch or could it be something else? This is my first time trying to tackle a problem like this on one of my vehicles. Any help is greatly appreciated and thank you in advance.
The under the hood fuses that are 10A ENG-E, 20A ECM-I and 20 A ENG-I are not getting power when the key is in the ON position. All of the other fuses have constant power. The fuel pump relay is getting constant power on pin 87 and not getting the "two second" power on pin 85 when the key is turned on. The pump does come on if I bypass the relay. The headlights are not automatically coming on when the key is in the ON position either. They do come on if I use the switch manually.
Using a test light, I had it stuck in the larger pink wire coming out of the fuse box. I accidentally touched the power post on the side of the fuse box and everything came on until I removed the test light from the power post. The key was in the ON position.
Does anybody have any idea what the problem might be? Is it the ignition switch or could it be something else? This is my first time trying to tackle a problem like this on one of my vehicles. Any help is greatly appreciated and thank you in advance.
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