LOW BEAM NOT WORKING

[Roger Bowton]

Our '06 Monterey was changed to a relay system as discussed in the forum, but the low beams are out.  There are three wires leading to the relays, from the dimmer switch. One goes to the high beam relay and one to the low beam relay, with one black wire being cut and taped off.   I  to am assuming this was a ground wire. There are wires running from the relay posts to ground in the electrical bay so I am  also guessing this wire does not need to be connected to anything, but I get no low beam.  Is there a way to trouble shoot the dimmer switch?  If I jumper the hot wire on the relay to the low beam wire from the relay, I get lights.  I have replaced the relay, and that did not help.  Any advice would be appreciated.

Roger

[JimDyer]

Hi Roger,

Normal operation of the dimmer switch would be that there are two hot wires coming from the dimmer- one is hot with high beams on and one is hot with low beams on. Switching the dimmer switch will switch the voltage from one to the other. Start by identifying these and marking them hi and Lo.

Then go to your relay setup. A relay works by toggling a switch when power is applied to the 'coil' side. You should have a relay for each of lo and high beam. (Or you could have a double relay, and some are built so that powering the coil switches the relay from one output to the other - in which case only the high wire from the dimmer would need to be connected. On the relay wiring diagram these would be marked as NO normally open and NC normally closed. Normally closed would be hooked to yout low beams and normally open would go to your high beams. The only problem here is that your low beams would be always on which is great if you want DRL's but most Americans don't.) The idea of the headlight relays is to take a 'fresh' source of 12v from the battery and feed it to the lights when the dimmer switch tells it to.......so your marked hi and lo lines should each go to the coil side of one of the two relays. The other side of the coil should be wired internally to the relay ground connection which I'm sure you can identify. If these are connected correctly, hitting the dimmer switch should switch the relay and the voltage should switch from the high beam line to the low beam line.

Clear as mud, right?

[Roger Bowton]

 I have two relays, and my problem seems to be that there is no voltage from the low beam switch wire going to the low beam relay.  I am now hoping that there is a remote dimmer switch and I don't have to pull the smart wheel to get at the dimmer /signal light lever.   I can't find any info on this

[Roger Bowton]

Does anyone know if there is a fuse in line for the headlights?  I got my low beam by wiring off of the low beam post in the electrical bay, but I get no power from the low beam wire, from the light harness going to the relay.

[JimDyer]

Have a look at the wires going to the high beam relay. Is there somewhere you can use a NC or NO output to power the low beams?

[Joel Ashley]

I dunno if this will help, but here is a link that may provide insight:

http://f1.grp.yahoofs.com/v1/YI_BTl1DYgw4CJ2grMYj9f2al_U_lyL_AIsxnWIZlW3cm70PuXhs1BePnva37moWk-8HZiW4arN6Vr3e5QPcWYs4TOzhGKX65Q/HeadlightWiringUpgrade/2002%20DSDP%20HEADLIGHT%20MODIFICATION.pdf

Joel

[Roger Bowton]

Joel

  Couldn't  get the sight to come up

Roger

[Joel Ashley]

Sorry not to have gotten back to you sooner, Roger;  had little available computer time lately.

I had minimal trouble opening the link directly off my post, so perhaps you don't have Adobe Reader, so you can open .pdf files?  Adobe Reader is available free online, but if you don't want to go that route, or there's some other glitch, try this non-pdf version:

http://www.danielsternlighting.com/tech/relays/relays.html

If you scroll down a ways, there are before and after circuit diagrams which may be helpful in troubleshooting components.

Joel

[Roger Bowton]

 Got  it this time.  
Thanks
Roger