[DSCHMAUS]

All the interior lights are working except the ones that light up the cluster (19a,b,c,d) If I turn the headlights on and rotate the headlight knob, the courtsy light will come on. I cant get the cluster lights to come one at all?

I checked the 2.5amp fuse and it isnt blown out...

What steps should i take to troubleshoot

Thank You

 

[mrchips]

if you have an older mustang see if you can pull out one of the lamps now run a jumper for a ground line to any part of the metal casing of the lamp to something else. if the lamp lights you know it could be the grounding of the cluster if it doesn't light check the wires down to the switch.use a tester for automotive use. I know one person who used a household tester after to day he called me to repair the lines and it was the power line from the switch.

 

[65fstbk]

The first place to start is to make sure the cluster is grounded...there should be a ground wire attached to the cluster and to the metal frome behind it..lots of times for one reason or another, that ground wire is not connected.if that checks out ok, another thing to check would be the cv (constant voltage) regulator mounted to the back of the cluster...Just noticed..you didnt specify a year (fill out your bio)..I would think that all years these would be the first 2 places to check, but I am not sure..I was refering to 65/66..on later years, I believe there is a printed circuit board that may also be the culprit...

Joe

 

[DSCHMAUS]

i'm sorry. Its a 67 mustang.. I will check the ground wire...

 

[DSCHMAUS]

The cluster is grounded fine.. is there a way to check the constant voltage unit?

 

[68Hardtop]

Use a voltmeter. That's likely your problem

 

[funjoh]

I am having the same problem, on an intermittent basis. I suspect the headlight switch. However, I will be checking out the ground.

 

[bostangman]

The constant voltage regulator only works the guages. It drops the voltage to about 4 to 5 volts by opening and closing contacts inside it very rapidly. Shouldn't be that.Try grounding the dash temporarly straight from a screw on the panel to the battery .

 

[DSCHMAUS]

Ok I will do that in the morning... If I have eliminated the ground as a problem would the next item be the head light knob (circuit)