Instrument cluster problems

[MAC390 327]

Car is running, these are the electrical issues i have.

Have a good printed circuit board and new voltage stabilizer

No dash lights , new globes fitted and i tested them in the sockets

Ammeter  works as do the indicators

When i hit the high beam floor switch the low beams go out and no high beam

All the other gauges don't work , nothing worked when i got the car.

Brake warning light comes on when i crank the starter

Just need a few pointers from the experts to speed up the work.

Thanks.

 

[Shep69 149]

1 hour ago, MAC390 said:

Car is running, these are the electrical issues i have.

Have a good printed circuit board and new voltage stabilizer

No dash lights , new globes fitted and i tested them in the sockets

Ammeter  works as do the indicators

When i hit the high beam floor switch the low beams go out and no high beam

All the other gauges don't work , nothing worked when i got the car.

Brake warning light comes on when i crank the starter

Just need a few pointers from the experts to speed up the work.

Thanks.

 

I'm no expert Mac but I assume that you've tried earthing out the fuel and water sender wires to see if your needles peg out. I purchased a new voltage reg and it was a dud out of the box. 

Make sure you are getting power into and out of the voltage reg. 

My brake warning light also comes on when cranking so  I think that's ok. 

Hopefully the Pink Flamingo will chime in on this one lol.

[MAC390 327]

Thanks Shep69, tomorrow i will investigate and definitely waiting for the Pink Flamingo to help me.

[Midlife 814]

Lots of unrelated problems.

1. Dash lamps.  Bad fuse, bad headlight switch, bad contact at dash cluster connector to circuit board.  Do other lamps on dash lamp circuitry work?

2. headlights and high beam: probably a bad dimmer switch.

3. Brake warning light while cranking: that's expected so long as it goes out when engine is running.

4. Gauges not working: briefly ground the sending unit lines when key is in ACC; they should peg.  If none do, it's probably the CVR or bad contacts on circuit board.

[Mach1 Driver 560]

Yep, Mid has it covered as always. If you want to SEE what the circuits look like, go to "How to's" on this forum, then the first pinned post called "A REAL Schematic". The dash lights and gauges are on page 2, while the headlights are on page 3. The 69s and 70s are very similar in these areas, except for the headlight changes- four vrs. two. The schematics are for a 69, although I did do another post on exterior lights for a 70 to show how their crazy side marker lights work.

[MAC390 327]

Thanks guys , the REAL Schematic helps.

Got dash lights, indicator lights come on when the headlights are used.

Put a test light on the instruments fuse in the fuse block and have no power on either side.

Does this indicate broken wire at fuse block on somewhere in the wiring loom.

[Midlife 814]

There is no fuse for the instruments in the fuse block.  I don't know where this notion comes from, but it is wrong.  WRONG, I say!

[Mach1 Driver 560]

8 minutes ago, Midlife said:

There is no fuse for the instruments in the fuse block.  I don't know where this notion comes from, but it is wrong.  WRONG, I say!

Mid, I think he may have misspoke; look on page 2: there is a fuse in the instrument light circuit, but not the instrument gauge circuit. The line from Light switch "I" it goes to 4A fuse #5, that feeds the ash tray light, heater light,  radio light, clock lights, and the 8 dash lights.

MAC390, which fuse are you talking about? Look at the position of the fuse in the block on the top of page 1. Since you have dash lights the fuse in question is probably not #5.

[Midlife 814]

Yes, there is a fuse for the instrument LIGHTS, but no fuse for the instruments themselves.  Mac's problem was that his gauges were not registering.

If Mac was trying to read the small fuse voltage and not seeing any on either contact, he probably did not have the headlight knob pulled.  He said the lights were now working. 

[MAC390 327]

Sorry guys, reading the schematics wrongly.(getting old)

What i have now is no power to the gauges, all sender wires dead .

Will check the gauge fitting in the housing to night.

 

[bigmal 225]

Hi Mac, I had no fuel/oil/temp gauges after changing the circuit board. I had a short between one of the posts for the gauges and the body of the instrument panel. If you use a multi meter and check betwwen the body and all 6 posts you should not have a direct short. The post easilly move around when the nuts are loose and can touch. One short takes out all three gauges. Once the short is removed mine worked normally.

[MAC390 327]

Mal , will check that out tonight thanks.

[MAC390 327]

Got the gauges centered in the housing, refitted the pcb and cvr.

No gauges, no power to the sender units wires.

Could this be an issue with the ignition switch or a wire coming off it as this supplies power to the gauge cvr.

I could be wrong , also i have fixed all the other electrical problems.

Thanks in advance.

[Mach1 Driver 560]

2 hours ago, MAC390 said:

could this be an issue with the ignition switch or a wire coming off it as this supplies power to the gauge cvr.

Sure. Power comes from ignition switch A on wire 297 to a splice, then goes through a 10 ohm resistor wire (#30 violet) and through the circuit board plug to the constant voltage regulator. Anything that interrupts that circuit could be the problem. Connect one lead of a voltmeter to chassis and start probing for voltage with the other lead. The plug doesn't appear to have numbered pins, but has a tab near one end. start counting at the end near the tab and count up 6 pins. That should be wire #30 violet. If you don't have power there with the ignition switch in "on or accy" then that's the problem.

[LoneWolf2U 136]

3 hours ago, MAC390 said:

Got the gauges centered in the housing, refitted the pcb and cvr.

No gauges, no power to the sender units wires.

Could this be an issue with the ignition switch or a wire coming off it as this supplies power to the gauge cvr.

I could be wrong , also i have fixed all the other electrical problems.

Thanks in advance.

Do you have the insulators in place on the gauges mounting bolts? they will ground out very easy without them.

No power out to the sending units as they are grounding for the gauge that allows it to read.

Is the harness to the cluster grounded?

[MAC390 327]

Put my old cvr on the printed circuit , got the pulsing from the cvr and power to the sender units.

The brand new cvr was one of those Chinese made crap , faulty straight out of the box.

Some of these parts are really sub quality for a high price.

Who has the best cvr to buy .

Thanks.

[unilec 57]

If you have a soldering iron just make your own.

http://www.mustangtech.com.au/Content/pid=28.html

[Shep69 149]

4 hours ago, MAC390 said:

Put my old cvr on the printed circuit , got the pulsing from the cvr and power to the sender units.

The brand new cvr was one of those Chinese made crap , faulty straight out of the box.

Some of these parts are really sub quality for a high price.

Who has the best cvr to buy .

Thanks.

Yep been there done that. I purchased an electronic one and it can be adjusted for fine tuning if required. 

[MAC390 327]

Hey Shep69,

What brand and where did you get it from

Thanks

[bigmal 225]

Hi Wal, I replaced my CVR and it turns out the old one was fine. You are welcome to have it. If you want to head down my way I'm home the next few days. Or I can express  post it to you today but you won't see it until mid next week. Alternatively Sydney Mustangs may be open today.

[Shep69 149]

2 hours ago, MAC390 said:

Hey Shep69,

What brand and where did you get it from

Thanks

Hi Mac. I purchased it off eBay in the US. Not sure of the brand. I've had it for a few years. There is one on the Aussie eBay site suitable for early falcons . That might work.

[danno 128]

On ‎12‎/‎17‎/‎2017 at 2:02 PM, bigmal said:

Hi Mac, I had no fuel/oil/temp gauges after changing the circuit board. I had a short between one of the posts for the gauges and the body of the instrument panel. If you use a multi meter and check betwwen the body and all 6 posts you should not have a direct short. The post easilly move around when the nuts are loose and can touch. One short takes out all three gauges. Once the short is removed mine worked normally.

I am not sure if you have these installed on yours on not, but there is supposed to be a rectangular insulator plate between the circuit board and the metal behind it for the gauges.  You can make them easily enough with a sheet of plastic, but you really need this.  You might get lucky for a while if you do not have it, but eventually the circuit will wear through to the metal behind it.  From the factory it was a piece of black, thin, cardboard, about 1 inch high by 2 inches long.  It has 2 holes in it for the screws that attach to the circuit board.

Make sure this is installed, it is number 6 on the list of common instrument panel problems.  The CVR is number 1.  Beer is number 2.

[MAC390 327]

danno, got all that covered, but where does Jack Daniels come in the list.