Dash warning lights & gauge question?

Have a few questions that came up trying to help them fig a dash issue.
1 - if a dash has warning lights where are they placed?

2 - if a dash has warning lights did it have a temp gauge?

3 - if it does have a temp gauge does it use a different IVR? I ask because Gary has it posted the IVR puts out a little under 6 volts to the "3" gauges - fuel / temp / oil.
So if a warning light cluster does have a fuel & temp gauges would the IVR be different?

4 - if you were to swap in a 4 gauge cluster besides needing to change the sending unit(s) oil and maybe temp, will it plug in and work or need to do something with the charging wiring because of the charge light will now be the ALT gauge.

Thanks for the help
Dave ----

Responses in bold

FuzzFace2 wrote

Have a few questions that came up trying to help them fig a dash issue.
1 - if a dash has warning lights where are they placed?  They replace the temp and oil pressure gauges

2 - if a dash has warning lights did it have a temp gauge?  No

3 - if it does have a temp gauge does it use a different IVR? I ask because Gary has it posted the IVR puts out a little under 6 volts to the "3" gauges - fuel / temp / oil.
So if a warning light cluster does have a fuel & temp gauges would the IVR be different? All of the IVR/ICVR's were the same: D1AZ 10804-A
4 - if you were to swap in a 4 gauge cluster besides needing to change the sending unit(s) oil and maybe temp, will it plug in and work or need to do something with the charging wiring because of the charge light will now be the ALT gauge.  You can't plug in a 4-gauge cluster as the wiring harness and connector are different.  Fewer pins in the idiot light connector than the gauge connector.  And, as you said, there's no key-on voltage to the regulator.  You'd either have to swap the whole cab wiring harness or make several wiring changes.

Thanks for the help
Dave ----

FuzzFace2 wrote

Have a few questions that came up trying to help them fig a dash issue.
1 - if a dash has warning lights where are they placed?

2 - if a dash has warning lights did it have a temp gauge?

3 - if it does have a temp gauge does it use a different IVR? I ask because Gary has it posted the IVR puts out a little under 6 volts to the "3" gauges - fuel / temp / oil.
So if a warning light cluster does have a fuel & temp gauges would the IVR be different?

4 - if you were to swap in a 4 gauge cluster besides needing to change the sending unit(s) oil and maybe temp, will it plug in and work or need to do something with the charging wiring because of the charge light will now be the ALT gauge.

Dave,

This topic came up on one of the Favebook Bullnose forums not all that long ago. A guy had purchased a replacement cluster with all 4 gauges and a tach to replace the standard warning light instrument cluster, and found out that the plugs were significantly different. I'm not sure what wiring changes are required, but they are are indeed required.

I took a quick look on Ebay and found a couple clusters with gauges that contradict what Gary says above. I can't say for sure that these are even out of Bullnose trucks, because Ebay often has medium duty truck clusters listed as Bullnose clusters...

They have fuel and coolant temp gauges, and warning lights for Oil pressure and Charge. So yes, they do have a temp gauge.

The two clusters would require different oil pressure senders (switches). Well, one is a "sender" I guess, and the other is just a switch, or at least that's how my local auto parts store identifies them. I assume the coolant temp sender is the same, and what wiring changes are required for the CHARGE light/gauge swap, I have no idea.

Pictures below, is this what you're curious about? The location of the gauges?

Cory - You know, in the light of day, you are right and I was wrong.  Looking at the 1981 EVTM the idiot light clusters did have fuel and temp gauges.  

Thanks guys,
When I first went thru Gray's post and saw "no temp gauge" I thought I found why the person was having issues with the temp gauge.
Then a little more reading of Cory's post and reply back from Gary the cluster did have the temp gauge.

So we are back at square 1 with this users issue with his 84 F150 300 six with warning lights.
After a short time running, less than 5 mins, the temp gauge will peg to hot but the motor is no where near even warm.
He has changed the sender 3 time but before installing he would test it by putting it between a 12 volt battery & meter. Thinking this was hurting the sender the last one went right into the block and did the same thing.

If he disconnects the wire at the sender the gauge goes to cold and if grounded goes to hot so the wiring and gauge check out.
He has also replaced the IVR a few months ago with no change.

We were thinking if he had to change out the gauge why not swap the whole cluster for gauges?
I thought if the cluster was swapped as a whole with the right circuit board and a change of the switches for senders would be ok other than the ALT wiring.
Now you are saying the trucks harness is also different between warning light & gauges so guess we will shelve that "fix".

Thanks again for the help.
Dave ----

Dave - I'll bet he's getting the wrong "sender".  There was the variable-resistance unit, which should show probably about 72 ohms when tested with a DVM, and there was also a temperature switch.  If he's getting the switch then it would peg the gauge as the temp comes up.

As you can see here (Electrical/Senders and the Coolant Temp tab), the one he wants has a green insulator.  Check it with a DVM to see if it has ~72 ohms cold.  If so it is the right one.  But if it shows a complete open when cold it is probably the switch.

Gary Lewis wrote

Dave - I'll bet he's getting the wrong "sender".  There was the variable-resistance unit, which should show probably about 72 ohms when tested with a DVM, and there was also a temperature switch.  If he's getting the switch then it would peg the gauge as the temp comes up.

As you can see here (Electrical/Senders and the Coolant Temp tab), the one he wants has a green insulator.  Check it with a DVM to see if it has ~72 ohms cold.  If so it is the right one.  But if it shows a complete open when cold it is probably the switch.

I don't remember if he posted the part number for it but all 3 times?
I guess it could happen I will pass on the information and hope it is that easy.

I did a little more look in the wiring area and for the 85 trucks, close enough for an 84 truck, it does show a 14 wire plug for warning light cluster and 18 wire plug for the gauge cluster so no way plug n play.

Thanks for your help.
Dave ----

EDIT: I just was going back over your post and getting confused, it don't take much  but wouldn't the variable-resistance one be for the gauge and the on/off switch for the light?

Then again we said the warning light cluster had a temp gauge so would it not work like the temp gauge in a gauge cluster? Why 2 different senders?
Even Auto Zone lists 2 different senders, gauges or with light?
This is crazy and no wonder why the gauge does not work right.

Maybe all three times if he told the same kid the same story.  Dunno.  But just check with a DVM as a switch will show infinite resistance and a sender will show around 72 ohms.

And, the '81 through '85 wiring will be the same in that area.  But, in '86 they eliminated the idiot lights.

Gary Lewis wrote

Maybe all three times if he told the same kid the same story.  Dunno.  But just check with a DVM as a switch will show infinite resistance and a sender will show around 72 ohms.

And, the '81 through '85 wiring will be the same in that area.  But, in '86 they eliminated the idiot lights.

I guess that could be easy enough to do,
az: gauges or lights?
person: it has a temp gauge
az: OK it is xxxx here you go!
and now we know if the truck has warning lights it does have a temp gauge but uses a different sender because of the warning lights.

That is why I like to look up the part numbers before I go so when they say something that don't quite sound right I can tell them the part number I want. If it is wrong then it is on me but I do check what their information has to say before taking said part.

Thanks again for the help
Dave ----

Stay OUT of the zone.  That's likely a BIG part of his problem.



It's relatively easy to re-pin the cluster connector(s) to work with the gauge cluster.  Collect some extra terminals in the JY to add any missing wires.

Steve - I assume that by “re-pin” you mean pull the wires out of the 14-pin idiot gauge connector and put them in an 18-pin gauge connector, and then add the needed other wires. Right?

Yep.  I hate cutting factory wires, but I love upgrading.

It's been decades, but I don't remember doing anything to my '83's cluster connectors any of the times I changed (factory) clusters.  But I don't remember what it had originally - I guess it might have had a non-tach gauge cluster, pre-wired for tach.  So that might be why everything I put in it was PnP (until the PSOM).

As I'm sure you know, lot's of the tach-less gauge clusters had the tach-capable printed circuit.  In fact, for the longest time I didn't understand what people were talking about when they were saying their circuit didn't have the traces for a tach.  All of the clusters I'd found did have the traces, even if they didn't have a tach.

But, then I ran into some w/o the traces and finally understood.  However, I don't know what the rhyme nor reason was for some having it and others not.  

Gary Lewis wrote

As I'm sure you know, lot's of the tach-less gauge clusters had the tach-capable printed circuit.  In fact, for the longest time I didn't understand what people were talking about when they were saying their circuit didn't have the traces for a tach.  All of the clusters I'd found did have the traces, even if they didn't have a tach.

But, then I ran into some w/o the traces and finally understood.  However, I don't know what the rhyme nor reason was for some having it and others not.  

That's interesting Gary. I didn't know that some of them had the printed circuit for a tach, even without the tach. My 1984 F150 did not have the printed circuit for the tach. I bought a complete 1984 Bronco manual trans cluster, and all I did was swap my KM speedo into the "new" cluster, and I was done like dinner.

Steve83 wrote

Stay OUT of the zone.  That's likely a BIG part of his problem.



It's relatively easy to re-pin the cluster connector(s) to work with the gauge cluster.  Collect some extra terminals in the JY to add any missing wires.

It would be nice to stay out of AZ but if they are the only one close then ......
After seeing what Gary posted and looking at the AZ site it is real easy to get the wrong one when all the trucks have a temp gauge bit the part is listed for lights?????

If I was going the try and re-pin the plug I would look into replacing the whole wiring harness but that's me, I have been known to do some crazy things
Dave ----

Like changing the firewall?  

Gary Lewis wrote

Like changing the firewall?  

Oh you remember that
I thought you were going to say using a style side metal ribbed floor in place of the wood floor the flare sides come with.
Dave ----

That too.  You don't do things the easy way.    Takes one to know one?

Birds of a feather, huh?  I catch flak from all my mechanic friends for taking a 600Kmi unrebuilt undersized underpowered engine out of a falling-apart truck, and putting it into a truck that I rebuilt from the ground up.  I'm not telling them (or you guys) what all I'm doing to the '95 F150 POS I just got...

Now you have our curiosity up?  A '95 F150?  With EFI?  Hmmmmm.....