Lost headlights and turn signals

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   Working on a 74 AMX w wiring issues.  Had headlights and turn signals. Suddenly they are both inop.  Hazard flashers work (swapped the flashers and hazard works w both).  Side markers and driving lights work (would indicate to me that bulbs are all good).  When going to the headlight position, the door open buzzer works.  Checked for voltage out of the headlight switch and it is there.  Removed one of the headlights and have no voltage.  Have not removed the grounds, but all was well previously. Suggestions?

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MartyB Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Apr/24/2018 Location: Plano, TX Status: Offline Points: 37	Post Options Post Reply Quote MartyB Report Post Thanks(0) Quote Reply Topic: Lost headlights and turn signals Posted: Oct/31/2018 at 4:21pm
	Working on a 74 AMX w wiring issues. Had headlights and turn signals. Suddenly they are both inop. Hazard flashers work (swapped the flashers and hazard works w both). Side markers and driving lights work (would indicate to me that bulbs are all good). When going to the headlight position, the door open buzzer works. Checked for voltage out of the headlight switch and it is there. Removed one of the headlights and have no voltage. Have not removed the grounds, but all was well previously. Suggestions?

304-dude Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Sep/29/2008 Location: Central Illinoi Status: Offline Points: 9082	Post Options Post Reply Quote 304-dude Report Post Thanks(0) Quote Reply Posted: Oct/31/2018 at 4:38pm
	you may have a bad fuse, check the connections and clean them for both fuse and the terminals.
	71 Javelin SST body 390 69 crank, 70 block & heads NASCAR SB2 rods & pistons 78 Jeep TH400 w/ 2.76 Low 50/50 Ford-AMC Suspension 79 F150 rear & 8.8 axles Ford Racing 3.25 gears & 9" /w Detroit locker

matty 401 Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jul/06/2007 Location: Iowa Status: Offline Points: 1727	Post Options Post Reply Quote matty 401 Report Post Thanks(0) Quote Reply Posted: Oct/31/2018 at 5:38pm
	dimmer switch ?
	72 matador 401 the beast 79 concord 2 door 72 matador 304 grasshopper 68 Rogue 406 93 Cherokee 4.0 5 speed

MartyB Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Apr/24/2018 Location: Plano, TX Status: Offline Points: 37	Post Options Post Reply Quote MartyB Report Post Thanks(0) Quote Reply Posted: Oct/31/2018 at 5:43pm
	Fuses are all good. 74 had the rheostat switch but it was trashed and replaced w one of the 71-73 switches. It seems to work as it will turn on the dash lights.

george w Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Joined: Jan/27/2013 Location: New Jersey Status: Offline Points: 2899	Post Options Post Reply Quote george w Report Post Thanks(0) Quote Reply Posted: Oct/31/2018 at 6:38pm
	Dimmer switch would be suspect if it weren't for the turn signals not working. Power leaves the dimmer switch and goes directly to the headlights. Not sure if AMC used a bulkhead wiring connector at the firewall in 1974. They didn't back in 69 and 70. If you have power coming out of one side of the dimmer switch then you must have a break or disconnection in the engine compartment portion of the harness between there and the headlights. Double check your voltage at the headlight plug. One connector is for low beam, another for the high beam and the third is the ground. You should see battery voltage at either the high or low beam terminal with the headlight switch on. Not sure of the wiring color code at the headlight plug but my guess is the all black wire is the ground so you'll want to measure at the other two terminals. If you don't show voltage at the plug then there's got to be a break in the feed wire(s). Got mice or squirrels around ?? To them wires and hoses are meat flavored.
	Long time AMC fan. Ambassador 343, AMX 390, Hornet 360, Spirit 304 and Javelin 390. All but javelin bought new.

Mopar_guy Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Joined: Jun/07/2009 Location: Ohio Status: Offline Points: 4826	Post Options Post Reply Quote Mopar_guy Report Post Thanks(0) Quote Reply Posted: Oct/31/2018 at 6:54pm
	The "dimmer switch" matty means the high low beam switch on the floor. With the headlight switch on you should have the center terminal show power along with one of the others depending upon the position of the switch. For the turn signals, check the terminal on the fuse box labeled turn signals to see if there's power going out with the key turned on. That's the first place to start. If not, check the fuse and the fuse holder for corrosion. If there is power there, check the turn signal switch connector on the side of the steering column. Unplug them and put it back together. I've seen those get pulled on and lose contact. It's best to use a test light with a bulb in it to test with. Try testing it to a good battery feed first to see how bright the bulb is, then check your circuits. If the bulb is dim, then there's high resistance in the circuit.
	"Hemilina" My 1973, 5.7 Hemi swapped Javelin

MartyB Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Apr/24/2018 Location: Plano, TX Status: Offline Points: 37	Post Options Post Reply Quote MartyB Report Post Thanks(0) Quote Reply Posted: Oct/31/2018 at 9:36pm
	Great info, thanks. Will let everyone know what I find when I can get to the vehicle again.

MartyB Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Apr/24/2018 Location: Plano, TX Status: Offline Points: 37	Post Options Post Reply Quote MartyB Report Post Thanks(0) Quote Reply Posted: Nov/11/2018 at 4:51pm
	Thanks for all of the suggestions. The dimmer switch is bad, power in, but no power out. Interesting that the dimmer switch is not even mentioned in the TSM! Still no turn signals. Have power to the fuse box and no power out to the headlight connection unless the ignition sw is in the on position, so that is all good. Unclear on the connector you are referring to. Is that the one attached to the side of the steering column or the one inside the column? Thanks. Marty

304-dude Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Sep/29/2008 Location: Central Illinoi Status: Offline Points: 9082	Post Options Post Reply Quote 304-dude Report Post Thanks(0) Quote Reply Posted: Nov/11/2018 at 4:57pm
	Wha? No head lights until ignition is on... not good. If it Is not the ignition switch causing the Issue it must be a wiring thing. All head lights should work with key out of ignition while in off. If you have a headlight delay module disconnect it and plug in the harness directly to the headlight switch. The delay plugs in, in series. It is a white opaque box mounted to the bottom edge of the frame under the dash, you will need to remove the bottom cover under the switches to see it. Edited by 304-dude - Nov/11/2018 at 5:00pm
	71 Javelin SST body 390 69 crank, 70 block & heads NASCAR SB2 rods & pistons 78 Jeep TH400 w/ 2.76 Low 50/50 Ford-AMC Suspension 79 F150 rear & 8.8 axles Ford Racing 3.25 gears & 9" /w Detroit locker

MartyB Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Apr/24/2018 Location: Plano, TX Status: Offline Points: 37	Post Options Post Reply Quote MartyB Report Post Thanks(0) Quote Reply Posted: Nov/12/2018 at 6:41pm
	Sorry, brain fart...meant to say I have power to the fuse box and no power to the turn signal connector on the fuse box until the the ignition sw is in the on position! As previously stated the 4 way flashers work so I assume the bulbs and ground (which I cleaned up) are good.