1964.5 Light Switch Help

[chris1973]

Hi guys

I've had a long running problem ever since I bought my car. When the headlights are on and at full beam, I have the gloriously dimly lit dash lights. When I have the headlights on dipped beam, the dash lights disappear. It means I have to have a speedo app on my phone running whenever I drive at night. It's been suggested that I changed the light switch, so I bought one when when in Florida at NPD. Despite showing them the photos below, taking the part number down, and assuring me the one they handed over was correct, I think they may have sold me the wrong one.

This shows the light switch in place, it's clear that the harness has been chopped about the the wires attached with spade connectors as it looks like there should be a shaped plug to fit onto the switch



This shows the part number on the old switch



This shows the terminals on the old light switch



This shows the terminals on the new light switch



This shows the part number on the new switch



I plugged the wires in where I thought they matched, but the new switch has an extra terminal so I left B empty. The headlights still worked on dipped and full beam, but the dash lights were dead. Plugged the old switch back in, same result. So the new switch is now back in the bag and my afternoon wasted :(

So, my questions are:-

Had I plugged the wires in right (leaving B terminal alone)? If so, I'll swap the switch over anyway.

Is the new switch right for my car or should I try to sell it and find another that matches?

As it made no difference to the dash lights, is this a pointless endeavour anyway?

Cheers

Chris

[Ryan McCully]

Light Switch

If your car is a 64.5 the light switch they sent you is correct. What has happened is that someone has changed the light switch for a later type one, in doing so they have decided to chop the wire plug off to make it fit. I only know this because I managed to buy the later type switch by accident, and now I have replaced it with an early switch. As for your dash lights, I cannot help as I haven't got this far in to the rebuild of my car yet, but I should think you are probably OK to use the switch you have got, but if you need the same as what you had, I still have got a brand new one in the box.

[chris1973]

Thanks Ryan, that's really useful.

So, do you think I'll find a stray wire that was not connected up to the new style switch, or was the extra terminal optional?

[barnett468]

hello

do you have a generator or alternator?

do you have stock headlites or halogens?

are you saying that you reinstalled your old lite switch and now your dash lites no not work at all?

a few things you can do are this.

check voltage at battery at idle.

increase rpm with idle screw to around and 2000.

check voltage

put lites on low and check voltage

out lites on high and check voltage

increase rpm slightly by opening therottle by hand and see if volktage increases.

post results.

remove the low instrument fduse from the fuse box and scrape the terminals with a small secrew deiver or dental pick to clean them, reinstall fuse and retry lites.

post a photo of your voltage regulator.

yes there should be a formed plastic plug that connects to the switch.





put lites onariund

[chris1973]

do you have a generator or alternator?

Alternator with integral regulator, fitting about a year ago by a professional auto electrician.

do you have stock headlites or halogens?

Halogens. I had them replaced months ago and took the opportunity to have relays fitted to protect the light switch. Before then, there were no relays.

are you saying that you reinstalled your old lite switch and now your dash lites no not work at all?

To be honest I haven't driven the car at night for a few months, so cannot guarantee the dash lights didn't work before. Also, I cannot guarantee they did not work when the dash was fitted back because they are too dim to see in daylight. By saying they did not work, I mean that the bulbs pulled from the back of the dash did not light when I had the lights on, but I'm not sure if they need to be in situ to make the relevant contacts.

check voltage at battery at idle.

increase rpm with idle screw to around and 2000.

check voltage

put lites on low and check voltage

out lites on high and check voltage

increase rpm slightly by opening therottle by hand and see if volktage increases.

post results.

This won't be possible until next week at the earliest, due to the fact my car is stored away from home.

remove the low instrument fduse from the fuse box and scrape the terminals with a small secrew deiver or dental pick to clean them, reinstall fuse and retry lites.

Thats a good idea. Again, I might be able to do this at the weekend. It will give me a chance to practice my contortionist skills again!

post a photo of your voltage regulator.

As the alternator has an internal regulator, I presume I won't have one. Is that correct?

yes there should be a formed plastic plug that connects to the switch.

I was going to get an old plug off a discarded harness, glad I didn't if the switch is wrong. At some point I do want to reinstate it to make changing it easier.

[cobraboy]

Chris
I think the dash lights have to be plugged into the unit to work as they earth through the panel.

Are you aware that the dash lights are on a dimmer ? this is worked by rotating the light switch, if it is turned all the way ( left I think ) it switches them off.

Experiment with it.

Randy at midlife wiring may have the correct plug for your car, but you may need to solder it onto your wires.

http://midlife66.com/harnesses/

[barnett468]

.
ok, well you have a bit of a fubar.

Your orig switch is correct for 64.5, the new switch is not but should be able to be made to work.

it looks like your number of wires to the switch is correct for a 64.5 also . . some of the wiring diagrams show 8 wires and 8 posts on the 64.5 switch which is incorrect.

The new switch has a brass post marked "R" . . this receives power which then goes to the coiled thingy on the back of the round white ceramic thingy . . the coiled thing is basically a resistor which regulates voltage to the dash lites.

The power comes out of the coiled thing and goes into the post that is rusty . . this receives a blue wire with a red stripe . . this goes to the fuse box fuse for the instrument lites only . . it comes out the other side of the fuse as the same blue with red stripe color which then goes to the instrument lites.

to find which wire should go to the "R" post to power the instrument lites just pull the headlite switch to the on position on your orig switch, then use a continuity checker and connect it to the front post that goes to the round wire thingy for the instrument lites and touch it to the other other posts one at a time . . only one post should have continuity.

find which color wire went to this post . . this wire must go to the "R" post on the new switch.

do the same test on the new switch, if it has 2 posts that have continuity with the post that goes to the round wire thingy, you need to add a jumper wire between those two posts so they are both connected.

The new switch receives power for the instrument lites [and the round wire thingy] from the brass post marked “R” . . the old switch receives it from another source . . this means that if you do not have power connected to the “R” post on the new switch you will not have instrument lites.

These lites are extremely dim when working properly so it is easiest to see them in the shade . . the darker it is the better, however, when driving at nite they should be clearly visible . . if they look really dim like a flashlite with a nearly dead battery, there is a prob . . one thing to check is to turn the headlite knob as cobraboy suggested . . one way is dim the other is full brite . . the knob will click into position when you turn it all the way in one of the directions . . I forgot which at the moment . . it is a bit hard to turn it to the clicked position and it may feel like the knob will break . . this is the direction that the instrument lites will be the brightest . . you can buy brighter bulbs but if they are too brite they will get hot and possibly discolor or burn something . . if you want to check the lites out of the instrument bezel, just run a jumper wire from the dash to the tiny metal base of the lite which normally grounds against the instrument bezel..

When you turn it until it clicks, it turns on the interior lites . . this is the only function of the “clicked” position.

Yes your alt has an internal regulator so you will not have one on the firewall, but I would still check the voltage . . even if it worked properly when installed who knows what is going on now.

Yes the bulbs must be in the dash to work as cobraboy suggested and the dash is ground by the two screws that go into the bottom next to the steering column.

your halogens have relays, this is good . . this along with the alternatiir suggests to me that neither of these items are the cause of your dim dash lites, but the lites should not go completely off no matter what position the lites are in unless you have them turned to a low setting by the headlite knob.


Here is an original NOS 64.5 switch if you want one . . imo, 129.00 is a smoking deal.

http://www.ebay.com/itm/NOS-Mustang-C5ZZ-11654-A-Original-Ford-Headlight-Switch-Assy-1964-1-2-/151541648933?pt=Motors_Car_Truck_Parts_Accessories&hash=item2348960e25&vxp=mtr#ht_230wt_1175

[chris1973]

I think the dash lights have to be plugged into the unit to work as they earth through the panel.

Thanks, that's what I wondered when I got home!

Are you aware that the dash lights are on a dimmer ? this is worked by rotating the light switch

Yes, I did know that. Well worth pointing out though, just in case

[Gazza51]

From memory your dash lights only worked when the switch was in the clicked position, I don't remember you having interior lights that worked.

I think the dash lights worked via the interior light circuit due to the wrong switch being previously fitted.

[chris1973]

From memory your dash lights only worked when the switch was in the clicked position, I don't remember you having interior lights that worked.

I think the dash lights worked via the interior light circuit due to the wrong switch being previously fitted.

If you had a look around my car when it was at Phil's, then you are right! The wiring is dead through the centre console to the rear interior lights, and the light in the passenger foot well is largely missing. It's an old car though, older than me, and its in a lot better shape despite some parts not working!

[Gazza51]

My point is your dash lights will most likely work if the switch is turned to the click position if using the switch that was fitted to the car when you got it ;)

[barnett468]

.
Ok, here is the correct 64 1/4 Mustang wiring for your original switch [both of which are the same as a 64 Galaxie] as you look at your switch as you show it in the photo . . The diagrams are hard to read so I didn’t post them . . This being said, if all the lights work properly, you might want to leave it alone.

Top row, left post - black/blue to courtesy lite and door lite switch.

Top row, right post - blue/red into fuse box then out from fuse box to instrument lites.

Second row, left side post that is bent down slightly - green/yellow to door lite switches, glove box lite as black and fuse block as green yellow . . The part on page 1 that says it turns to yellow/green after leaving the switch is incorrect.

Second row middle post - red/yellow to high/low headlite floor switch.

Third row, right post – solid black to tail lites and license lite.

Bottom row, left post near center - black/yellow to front signal/park lites for parking lite only.

Bottom right post - black/orange which splits off into 3 wires . . One turns into solid yellow which goes to ignition switch, one stays black/yellow and goes to the fuse box and the other stays black/yellow and goes to original generator voltage regulator [which you not longer have] where it comes off as two wires, one is solid yellow which goes to the horn relay and the other is a large diameter black/yellow that goes to the large front post on the starter solenoid where the battery cable also mounts.


On a 65 and later, the green/red stop lite switch is connected to the bottom/rear left post [with the knob up and the posts facing you] on the headlite switch along with the solid yellow wire that goes to the horn.

[barnett468]

If you had a look around my car when it was at Phil's, then you are right! The wiring is dead through the centre console to the rear interior lights, and the light in the passenger foot well is largely missing.

you can get possibly get an aftermarket courtesy lite assy from the local parts shop if needed.

The round spring thingy mounted on the white ceramic on the back of the switch has a small delicate arm that has a tiny contact on the end that rubs on it . . both these items sometimes get dirty causing problems with the interior lites . . you can gently clean the contact on the arm by installing the knob for the switch, this will hold the ceramic assy steady, then slide a piece of around 400 grit black sand paper between the spring and the contacts then slide it up and down a little . . don't double it to sand the spring at the same time, it might damage the contact arm.

Next, double the paper and rub it on the spring lightly then spray it with contact cleaner.



The following will get power to the console and shifter lites . . There may be a plug under the dash to connect to the console harness though.

blue/red from instruments is the power wire for the shifter lite.

black with black connector from shifter to goes to ground.

black/blue from the under dash courtesy lites is power and goes to the rear console lites.

The other wire from the rear console lites goes to ground.

If your console has the wiring, there will be a ground wire in the harness with a loop on one end.

If it has a storage compartment, the compartment lite has a green wire which connects to the green/yellow wire that goes to the door lite switches and fuse box . . it is full time power . . the lite comes on when the storage door is opened . . there is a piece on the lite that needs to be grounded.

[chris1973]

I hoped I'd have a chance this weekend to investigate, but no chance. Next weekend I'm in Wales at a funeral, so this will have to wait a few weeks :(