A soon as I hit the switch on the column it blows both 10a fuses. Blue hi beam indicator light remans lit on dash. The two fuses are adjacent to the DIM relay in the fuse panel They are labeled H-LP HI RH and LH. More craziness with the most over designed lighting system ever. Any thoughts on what to check next? This is of course the HID system on a 2009.
Though's two fuses operate the shade actuators in the headlamp. It would be most unlikely that they both would go short circuit so I would suggest looking for damaged wiring (possibly mice) under the fuse box. The wires are colored violet and yellow in the circuit bellow. Disconnecting at the headlamp end would be a good starting point to see if the fuses still blow. John (Britprius)
Yes the headlamps stay lit when fuse blows. I inspected wire harness. No visible damage under fuse panel. Ipulled the plug at headlight on drivers side. Hard to pull plug on right without removing some stuff. i put a fresh fuse in the fuse location labeled LH and hit the high beam switch. It blew immediately. Does this point to anything? Is there a different plug that goes to the shade actuators? Thanks, Bob
As we do not have OEM HID's in the UK so I have not seen how the connections are made, but I would assume the shade actuators are on a separate plug to the HID bulbs. If you can find and pull those plugs try refitting the fuse and then operating high beam. If the fuse blows without the actuators connected the fault is in the wiring, if the fuse does not blow connect the actuators one at a time to find out which one is faulty. I am afraid I do not know if the actuators can be changed or if it is a case of a new headlamp unit. John (Britprius)
You Brits are fortunate Toyota did not plague you with HID. I will never have HID on a vehicle again. This latest problem is one in a long line of a ridiculously over engineered system. I will try to find actuator connection. Thanks, Bob
Not that I'm aware of. Your's re the first cases I have heard of on PC but I could be wrong. Of course the number will be limited because it will only affect those with OEM HID lamps. I have fitted aftermarket HID's to my own Prius and would not go back to OEM halogen bulbs. Aftermarket HID bulbs are little more in cost than the halogen. The complete kit including two inverters, two bulbs, and wiring harness with relays being only £22- $35. John (Britprius)
Having read your post again if both fuses are blowing it is difficult to see what could be blowing both fuses. I would have thought it most unlikely that both actuators would be short circuit, and as you can see from the circuit the only wires they feed are the yellow and purple one's at the bottom right of the circuit. All the other wires in that part of the circuit do not actually exist, only being there with halogen lamps. John (Britprius)
I know this thread is more than a decade old, but I have the solution, which may be of help to others. My HID high beams were also not working on my 2007 Prius. I had reasoned that since it was both not working, it must be the relay. The really checked fine. Then I found both 10 amp fuses blown. The fuses are right next to the relay, which is labeled DIM in the under-hood fuse box. Those fuses are located after the line splits to the two headlights, and go to the high beam actuator in each headlight, which is just a solenoid. The wire goes in at the bottom of the headlight through a plug that is not on the large round cover, then another cable inside the unit goes from that outside plug to the solenoid, which is located under the HID headlight bulb. I disconnected this plug, replaced the 10 amp fuse, then turned on the high beams. The fuse was still good. I then connected the solenoid plug and activated the high beams again and the fuse blew immediately. I had the same experience on both sides. Good thing I bought the 5 pack of fuses. So that pointed to the actuators themselves. With the headlight removed from the car, and turned over, with the large round cover removed, the solenoid is on top protruding a little from the enclosure. It can be worked on right where it is. Some light prodding revealed that they were not physically stuck in any way. So I plucked open the plastic cover on each of the solenoids. This is done by lightly pressing upward on the edge closest to the coil (the big white part) to unseat the two holes in that cover from the two little nubs on the rest of the enclosure, then press it back away from the coil and toward the enclosure. NOTE: The picture of my prying off the plastic lid was taken AFTER I fixed the actuator. It shows the new black and silver diode in place of the original blue and white diode. Yours will have a blue and white diode there. This reveals two diodes. On my car when I checked the resistance of the large diode that goes from the black wire (middle pin) to the third "pin" (the one at the top with no wire on it.) it checked 6.65 Mohm on one headlight and 7.35 Mohm on the other. When I checked resistance on these in the opposite direction, they were infinite resistance. (this is good since diodes are supposed to only pass juice in one direction.) The second diode, going from the third pin to the red wire, measured no resistance in either direction. That is not good. It was essentially shorting the circuit so no juice would travel through the coil, which is wired between the third pin (at top of pictures) and the red wire pin (at the bottom of the pictures). A little research revealed that this diode is there to absorb voltage spikes traveling back through the wire as the circuit is shut off, and let them bypass the coil. (I am not an electrical engineer, so I might be wrong on that.) These diodes are not soldered in. They are simply pressed down into two V shaped metal tabs. They can be pried out with a pick like I am doing in the first picture. A new diode can then be pressed in with a razor blade or something pointy. Be sure to place the ring on the side by the red wire as in the picture with the black and silver diode. I used a 1N4001 diode. I had looked for a 1N4007, which should be hardier, but this was all I could find locally. It worked and was available for under a buck at the local radio repair shop. I'm sure you can also get them online. Once you press the new diode in, put the plastic cover back on, put it back together, replace the 10 amp fuses if necessary, and test it. I was sure to hold my headlight enclosure close to level as I am not sure if the linkage and orientation of the shutter would put undue burden on the solenoid if the headlight were sitting perpendicular to the normal orientation. As for the reasoning that the fault likely isn't in the enclosure since they both went out at the same time, I suppose it is possible that one voltage spike killed both, or that if one dies, it is easier for the other to die since they do share a common feed wire back at the relay. I'm no expert, but I know both of mine were dead at the same time. Good luck.
