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Tron Man · 11-02-2015, 03:16 PM

Oliver, let's address the head lamp problem first. Since your grounds look OK remove the RH head lamp and examine the connector for corrosion. If the connector is clean the lamp is most likely has a open low beam filament. To make sure the lamp is defective you can check for voltage at the connector. Your head lamp low/high beam connector has three wires. Black=ground, Tan=low beam and Light Green=high beam. With the head lamp switch on and the dimmer switch on low beam, measure the voltage at the Tan wire connection to ground. If you measure 12 volts, then replace the head lamp. If you don't see 12 volts, then you'll have to find out why.

If your turn signal flasher is loose on the fuse panel, the female spade connectors located in the fuse panel may be spread out (loose) or broken. With the ignition switch off, probe each spade connector carefully and gently with a blade tip jeweler's screw driver and see if you can slightly bend each side of the female spade connectors toward the center. Again be very careful here. If this process doesn't work you may have to shim one or both flasher spade terminals with thin metal strips to tighten the connection.

As far as flashers go, there is a difference between turn signal flashers and hazard flashers. Turn signal flashers are wired in series within the flasher can and hazard flashers are wired in parallel in the flasher can. Again the reason for the difference is the series wired turn signal flasher will only flash if the front and rear turn signal bulbs are working. If one of the turn signal bulbs is burnt out, there is not enough current drawn through the flasher's heater element to activate the bi-metallic strip inside the flasher can. In this condition the driver will see a constantly lighted turn indicator on the dash indicating the a front or rear bulb is not working. A hazard flasher will work with burnt out bulbs or not due to the parallel wiring arrangement within the hazard flasher can. In summary a hazard flasher will work for turn signals, but the burnt out bulb indicator feature won't be available.

Let me know how you make out with the head lamps and turn signals. We'll keep pushing on these issues if need be.

Tron Man,
Reno Nevada

11-02-2015, 03:16 PM	#8
Tron Man Registered User Join Date: Sep 2015 Location: Reno, NV Posts: 7	Re: First Truck Electrical Issues Help! Oliver, let's address the head lamp problem first. Since your grounds look OK remove the RH head lamp and examine the connector for corrosion. If the connector is clean the lamp is most likely has a open low beam filament. To make sure the lamp is defective you can check for voltage at the connector. Your head lamp low/high beam connector has three wires. Black=ground, Tan=low beam and Light Green=high beam. With the head lamp switch on and the dimmer switch on low beam, measure the voltage at the Tan wire connection to ground. If you measure 12 volts, then replace the head lamp. If you don't see 12 volts, then you'll have to find out why. If your turn signal flasher is loose on the fuse panel, the female spade connectors located in the fuse panel may be spread out (loose) or broken. With the ignition switch off, probe each spade connector carefully and gently with a blade tip jeweler's screw driver and see if you can slightly bend each side of the female spade connectors toward the center. Again be very careful here. If this process doesn't work you may have to shim one or both flasher spade terminals with thin metal strips to tighten the connection. As far as flashers go, there is a difference between turn signal flashers and hazard flashers. Turn signal flashers are wired in series within the flasher can and hazard flashers are wired in parallel in the flasher can. Again the reason for the difference is the series wired turn signal flasher will only flash if the front and rear turn signal bulbs are working. If one of the turn signal bulbs is burnt out, there is not enough current drawn through the flasher's heater element to activate the bi-metallic strip inside the flasher can. In this condition the driver will see a constantly lighted turn indicator on the dash indicating the a front or rear bulb is not working. A hazard flasher will work with burnt out bulbs or not due to the parallel wiring arrangement within the hazard flasher can. In summary a hazard flasher will work for turn signals, but the burnt out bulb indicator feature won't be available. Let me know how you make out with the head lamps and turn signals. We'll keep pushing on these issues if need be. Tron Man, Reno Nevada