RX-7 FC Headlights not working!
12-06-10, 08:27 PM
#1
RX-7 FC Headlights not working!
Ok heres the story i turn on the headlight swich all the way all lights work on the interior as well as tailight side markers ex,Ecept no headlights the dont come on nor pop up but if i use the other swich that raises and lowers the headlights they will go up and down, i can also use the high beam swicth and it works, puzzled to what this could be i read somewhere on the forum of people saying the headlight relay will cause this but im unsure where it is located, Any help would be appreciated. Thanks!
12-06-10, 08:44 PM
#2
Looking at your profile it indicates that the car is an S4. Given this there are a few things to look over. The headlight relay is located in front of the radiator near the front nose piece and is the second from the left when looking from the front of the car (there will be a group of relays there). The relay has 4 wires. Two of them are Red, one is White/Blue and the last wire is Red/Green. Take a short jumper wire and jumper one of the RED wires to the Red/Green wire while the plug is connected to the relay and see if the lights turn on and also measure for voltage on both of the Red wires before adding the jumper as there should be battery voltage w/no key necessary. Also, with no key necessary take a longer lengthed jumper wire and place one end into the back of the plug where the White/Blue wire is and touch the other end of the wire to a known ground such as the alternator housing or negative battery terminal to see if the lights turn on and do this w/o the other jumper wire connecting the Red wire to the Red/Green wire.
12-06-10, 09:48 PM
#3
RX-7 Headlights not working.
Thanks for the info! I think what happened is im doing a ground up restoration and iv ben replacing and upgrading different things in the car and i put in a S5 guage cluster and may have damaged something when doing so, when plugging and replugging the harness so im hopeing it may just be the relay because it was working fine before that.
08-20-12, 01:25 PM
#4
Full Member
Looking at your profile it indicates that the car is an S4. Given this there are a few things to look over. The headlight relay is located in front of the radiator near the front nose piece and is the second from the left when looking from the front of the car (there will be a group of relays there). The relay has 4 wires. Two of them are Red, one is White/Blue and the last wire is Red/Green. Take a short jumper wire and jumper one of the RED wires to the Red/Green wire while the plug is connected to the relay and see if the lights turn on and also measure for voltage on both of the Red wires before adding the jumper as there should be battery voltage w/no key necessary. Also, with no key necessary take a longer lengthed jumper wire and place one end into the back of the plug where the White/Blue wire is and touch the other end of the wire to a known ground such as the alternator housing or negative battery terminal to see if the lights turn on and do this w/o the other jumper wire connecting the Red wire to the Red/Green wire.
08-20-12, 02:53 PM
#5
Sorry to high jack and open this dead tread.. I just tried what Satch said and with the jumper with the white/blue and ground and my lights come on... If i'm not mistaken wouldnt the white blue wire be ground??? so would this mean that the relay is not getting ground from the headlight switch.. when tried you should hear the relay click
11-16-13, 09:53 PM
#6
sorry to bring this back from the dead again..lol
ive tested both red wires for power and the white wire aswell and have power on all three. I also have power on RG when grounding the WB wire. relay clicks an all.
But ive still got no lights..so if like he said the headlight switch acts as a ground for each wire, and my relay is clicking. That means the switch is doing its job in passing ground correct? soo..since i have no lights in any test does this mean both Relay and Switch are okay? if so where would the next call the action be from here?
ive tested both red wires for power and the white wire aswell and have power on all three. I also have power on RG when grounding the WB wire. relay clicks an all.
But ive still got no lights..so if like he said the headlight switch acts as a ground for each wire, and my relay is clicking. That means the switch is doing its job in passing ground correct? soo..since i have no lights in any test does this mean both Relay and Switch are okay? if so where would the next call the action be from here?
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11-17-13, 09:13 AM
#9
If you can get power at the R/G wires of the Headlight Relay then that voltage passes on to the Dimmer Relay such that the Red/Black wire at this relay has voltage when the low beams are to be on and the Red/White wire would be the wire having voltage when the high beams are activated so check the R/B first and then turn on the high beams and verify that the R/W wire has voltage.
11-17-13, 12:58 PM
#10
If you can get power at the R/G wires of the Headlight Relay then that voltage passes on to the Dimmer Relay such that the Red/Black wire at this relay has voltage when the low beams are to be on and the Red/White wire would be the wire having voltage when the high beams are activated so check the R/B first and then turn on the high beams and verify that the R/W wire has voltage.
I unbolted the dimmer relay and probed bother R/B and R/W. Neither show voltage with the headlight switch off which is normal.
Switch headlight to low beams and I have 12.07v at both R/B - R/W.
Toggling my highbeams has no change.
I went to take a look at the wiring diagrams in the FSM and am having a hard time trying to understand how to decipher them. lol
FWIW im looking at the diagrams as you instruct on here so i can slowly figure this all out
11-17-13, 01:31 PM
#11
For one thing you shouldn't have voltage on both R/B and R/W at the same time as it is an either or type of situation. The relay contact inside dictates which of these wires gets the voltage. Not really sure how both have 12 volts w/just one contact inside. The White wire in the plug dictates which wire gets the voltage. W/the White wire receiving a ground the relay contact should switch positions and pass voltage to the R/W wire and this occurs by activating the high beams. You might want to try and use the negative battery terminal for a ground source and see if you can get the relay to switch contact positions which would make the relay choose as to whether it is going to place the voltage on the R/B wire or the R/W wire (ground the White wire to do so). In addition there are three wires at each headlight. Black is the ground and the other two wires are R/B and R/W from the Dimmer Relay. If both R/B and R/W had voltage you would think both filaments in the headlight would turn on so it seems a bit strange that it does not happen and maybe them both having voltage at the same time burned out the filaments withing the light.
11-17-13, 02:04 PM
#12
Ok so I had the headlight switch on lowbeams for whatever reason and grounded the white wire on the dimmer relay and it clicks but nothing happens lighting wise.
ok...so here is what im doing right now. i have the low beams switched on. While grounding out the white wire I am measuring voltage on both RB and RG.
When i check voltage on the RG, the relay clicks and the voltage drops from 12.10v to 12.08v
when doing this same method to the RB the same happens but the voltage reads 12.07 and drops to 12.05. I feel that was a bit irrelevant though haha.
so im pulling my headlamps out now. if i ground either RB or RG at the headlamp connector i should....well well well just pulled my pass headlight and found this.
First is the pass side and the secon is drivers..what would cause the both ground wires to burn to crisps?
ok...so here is what im doing right now. i have the low beams switched on. While grounding out the white wire I am measuring voltage on both RB and RG.
When i check voltage on the RG, the relay clicks and the voltage drops from 12.10v to 12.08v
when doing this same method to the RB the same happens but the voltage reads 12.07 and drops to 12.05. I feel that was a bit irrelevant though haha.
so im pulling my headlamps out now. if i ground either RB or RG at the headlamp connector i should....well well well just pulled my pass headlight and found this.
First is the pass side and the secon is drivers..what would cause the both ground wires to burn to crisps?
11-17-13, 04:18 PM
#14
Not really sure about the burning wire aspect but if you had both headlights unplugged does it change in anyway how the R/B and R/W wire behaves at the Dimmer Relay or is it the very same?
In seeing your last post it is possible that the grounds being damaged caused a loop of voltage from the R/B wire of the Dimmer Relay to the headlight to the R/W wire and back to the relay. Just a thought though. You also might want to check the other end of the ground to make sure it is a solid and clean one. Ground position #5 is where both of these Black wires meet and the final grounding point is a bundle of 5 Black wires that are in a plug that mates to a metal block which is then bolted to the trailing coil side of the strut tower so at that side of the tower and between and below the trailing coil is where the headlight grounds originate.
In seeing your last post it is possible that the grounds being damaged caused a loop of voltage from the R/B wire of the Dimmer Relay to the headlight to the R/W wire and back to the relay. Just a thought though. You also might want to check the other end of the ground to make sure it is a solid and clean one. Ground position #5 is where both of these Black wires meet and the final grounding point is a bundle of 5 Black wires that are in a plug that mates to a metal block which is then bolted to the trailing coil side of the strut tower so at that side of the tower and between and below the trailing coil is where the headlight grounds originate.
Last edited by satch; 11-17-13 at 04:46 PM.
11-17-13, 05:12 PM
#15
oh yea. i know whch ground your talking about.
Ive cleaned that ground up not too lon ago so it is well. Although maybe i should do some resistance checking from there to the grounds on the headlights to see what im working with.
Since swapping in new connectors the dimmer relay is reading correctly now.
My last electrical problem i have now is my driver turn signal keeps blonking fast like a burn bulb. Ive been fighting it since i purchased the car 2 years ago. new bulbs, new sockets and swapped turn signal relays. I hve yet to test the wiring though as i have still not figured out how to read the wiring diagrams
Ive cleaned that ground up not too lon ago so it is well. Although maybe i should do some resistance checking from there to the grounds on the headlights to see what im working with.
Since swapping in new connectors the dimmer relay is reading correctly now.
My last electrical problem i have now is my driver turn signal keeps blonking fast like a burn bulb. Ive been fighting it since i purchased the car 2 years ago. new bulbs, new sockets and swapped turn signal relays. I hve yet to test the wiring though as i have still not figured out how to read the wiring diagrams
11-17-13, 05:40 PM
#17
yeap. basically the symptoms you get when you have a burnt bulb. all parking lights work, but the drivers turn signal seems to only want to use one filiment instead of using both.
Instead of being lit and then getting brighter like they would normally do it does the opposite and goes dim with the flash
Instead of being lit and then getting brighter like they would normally do it does the opposite and goes dim with the flash
11-17-13, 08:07 PM
#18
Do you have the same bulb in the front as the back? I know the front marker lights up w/a low brightness w/the driving lights on and flashes w/a higher brightness when signaling for a turn but the rear bulb only lights up when signaling for a turn and doesn't light up w/the driving lights on.
11-17-13, 08:55 PM
#20
Have you thought about taking the front bulb from the good side and switching it to the non working side. And at the CPU plug the wire for the driver side is G/B and the other side is G/W. If you're good at removing pins you could remove both and then place the G/B wire to the former spot for the G/W and see if that changes things. If it works properly that rules out the bulbs and wiring and places more emphasis on the relay.
11-17-13, 09:02 PM
#21
Have you thought about taking the front bulb from the good side and switching it to the non working side. And at the CPU plug the wire for the driver side is G/B and the other side is G/W. If you're good at removing pins you could remove both and then place the G/B wire to the former spot for the G/W and see if that changes things. If it works properly that rules out the bulbs and wiring and places more emphasis on the relay.
I shall try swapping them around once i locate my pinning tool. If i remember correct theres 4 wires on this plug, what are the other two if two already are for the lights? signal wires?
11-17-13, 09:30 PM
#23
ok so can you give me a quick run down on how the turn signals work?
I hit the turn signal which the wires then run to the relay that then trigger power to the corners of the car? or does the turn signal lever itself simply act as a ground like the headlight switch does for the low and high beams?