MENU Subscribe to a Magazine
  • Sign in
  • Join

Subscribe to Print or Digital! Save up to 83%

Magazine Muscle Mustangs & Fast Fords
Magazine Mustang Monthly
Magazine 5.0 Mustang & Super Fords
Magazine Modified Mustangs & Fords
  • Print Subscriptions
  • Digital Subscriptions
  • Gift Subscriptions
  • Subscriber Services
  • Back Issues
  • Personalized Cover
  • Subscribe to a Magazine
Item Posts    Sort Order

69 mach1 instrument panel not lighting up

 
paultrav
New User
Posts: 5
Joined: 01/12
Posted: 12/08/12 02:00 PM

I was getting some lights to work for the gauges, but after installing LEDs and cleaning all contact points, I get no lights.  Trying to learn how to use the GMT-312 to determine what jack points (1-18), where it contacts the instrument circuit board, are providing what power purpose.  I now am looking for a new circuit board and just ordered a headlamp switch rheostat assembly.  I did ground negative  battery terminal to both the block and the anchor point of the passenger side headlamp.  Any suggests on why I can get anything working is greatly appreciated.  

Post Reply
waynep71222
Enthusiast
Posts: 455
Joined: 04/12
Posted: 12/08/12 06:45 PM

well... are you running a standard headlight switch..

power comes into the headlight switch ... when the parking or headlights are on.. the big resistor gets powered...   output from the resistor goes through the fuse box instrument fuse.. its the smallest fuse.. and on to the cluster illumination bulbs...

so do the other lights work.. do you get variable voltage at the shortest fuse when the headlight knob is pulled out and you rotate the knob???

ground connections...

between the negative battery and the body.. usually at the inner fender well..

between the back of the engine and the  firewall...

does your engine run??? and the charging system work..

i have a voltage drop test that takes just a few minutes if you have a digital volt meter to verify the grounds are proper ..

at least the main grounds...

Voltagedroptesting  

Post Reply
paultrav
New User
Posts: 5
Joined: 01/12
Posted: 12/09/12 04:44 PM

Thank you for your advice and three minute check list I haven’t finished yet.  I think I sheared something in the standard headlight/rheostat gismo when putting it back together.  I forgot about the spring retainer pin on the assembly body and pushed to hard I think.  The knob pin won't lock onto anything now.  Ordered a new switch assembly.  Still looking a for an instrument panel circuit board replacement.  Just eyeballing I see a brake in the top copper line in the plastic.  I think I will get a digital meter as well.  I can't see how to measure 12.65 with my needle reading version.  I found the fuse box and the smallest fuse you mentioned was missing.  I did have luck at one point with the LED lights for the speedometer and alternator working and right hand turn signal, seatbelt, and brake system display light as well without that little fuse there.  Now only the RH signal, and high beam indicator light up without the fuse (I'm yet to have that size fuse).  I hope to find what the numbers (1-18) on the wire jack for the instrument circuit board represent.  After the pieces arrive, I will post an update.   Thanks again.  

Post Reply
waynep71222
Enthusiast
Posts: 455
Joined: 04/12
Posted: 12/09/12 05:46 PM

you might want to read this thread a few months ago... on 69 dash board printing circuits...

http://forums.mustangmonthly.com/70/9288567/mustang-restoration/instrument-cluster-wiring/


this covers a replacement harness for the WRONG Cluster...  

Post Reply
paultrav
New User
Posts: 5
Joined: 01/12
Posted: 12/10/12 09:29 PM

Thanks again, I haven't checked to see if the cardboard spacers for the gauge bolts have wilted.  I have taken the instrument assembly out several times and may have bumped it.  I'm thinking while waiting for the circuit board and headlight switch, now is a good time to get the stock PHILCO am rebuilt for fm as well as try cleaning the clock before going digital. Would you have suggestions on who to do that or past postings on how?  Any suggestions on what other components I should order while the dash is out is appreciated.  

Post Reply
paultrav
New User
Posts: 5
Joined: 01/12
Posted: 01/01/13 09:35 PM

I was fortunate with the new circuit board and LED lights.  Nice to see bright panel.  But I am having problems with the headlight knob command shaft catching on the retaining pin in the new rheostat assembly.  I am using the original rheostat again (was going to replace it just in case).  I also am trying to clean out and oil the clock assembly, but can't straighten out the bent-in metal housing tabs used to retain the plastic clock face.  They seem to spring back after prying them out.  I almost broke the clock face from tension.  Any secrets for disassembling/cleaning would be gratefully appreciated.  

So Im thinking that now is the time to change the 40 y/o vacuum hose controlling the ac/heat assembly, but I can't figure out if I can take the hoses off the rubber block/manifold that the hoses gather at for the control lever.  I haven't tried the actuators on the assembly and hoping they will work.  

Post Reply