F439789 Report post Posted August 30, 2020 (edited) headlights, tail lights and running lights won't work, turn signals, flashers and brake lights are ok. have checked all fuses that i can find, they are good. 08 phaeton 36 ft qsh on spartan chassis, Edited August 30, 2020 by F439789 Share this post Link to post Share on other sites
kaypsmith Report post Posted August 30, 2020 Most likely these have both a circuit breaker and also a relay. If there is a short (hot to ground), then the circuit breaker will trip causing nothing to happen. If you have a bad switch the relay cant activate because no voltage to engage it. So the first place to check is the switch to make sure that you have voltage to the switch, then voltage away from the switch when in the on position. If no output from switch, bad switch, if no voltage to the switch then you must trace back to the battery source. If further help is needed, just ask, let us know what you find. Share this post Link to post Share on other sites
F439789 Report post Posted September 1, 2020 fuses are all good, switched relay from a system that i know is working, nothing changed. checked power to switch, it's good, checked power out of switch with 12v test light and it shows power when switch is turned on and off. totally perplexed Share this post Link to post Share on other sites
dickandlois Report post Posted September 1, 2020 (edited) On 8/30/2020 at 12:09 PM, F439789 said: headlights, tail lights and running lights won't work, turn signals, flashers and brake lights are ok. have checked all fuses that i can find, they are good. 08 phaeton 36 ft qsh on spartan chassis, Does you coach have a ICC switch ? Not all work the same way, but it is worth checking out. Look at this link. Did it drink some coffee or tea by chance? Rich. Edited September 1, 2020 by DickandLois Share this post Link to post Share on other sites
kaypsmith Report post Posted September 1, 2020 If all else fails, time to look for a circuit breaker, headlights are rarely fused. The circuit breakers are usually small square plugged directly into the fuse panel for chassis. These are after the headlight switch and will reactivate when cooled down unless bad. Share this post Link to post Share on other sites