67 headlight switch w /U17 console instruments

[big iron]

Does anyone know why there are 2 67 headlight switches. Std.1995147 and 1995149 w/U17. Does the 149 have a higher rated light dimmer for the console ? See VPC 12 B6 and revision 4.

[tom]

Ralley Sport headlight door control would be my guess.

[JohnZ]

Does anyone know why there are 2 67 headlight switches. Std.1995147 and 1995149 w/U17. Does the 149 have a higher rated light dimmer for the console ? See VPC 12 B6 and revision 4.

The November, 1968 parts book shows one switch for all '67 Camaro applications (#1995164, which superceded #1995149).

[big iron]

JohnZ,
The 68 AIM 12 B6, revision 1, Dated 6-29-67, verifies what you said is correct. My 69 parts book also gives the 164 as the correct number.
Was the RS option available at the start of production on the 67?
Tom,
Looking at the std. and RS wiring diagrams, shows no need for a different switch (all wiring is the same at the switch).
Maybe someone with a 67 parts book could see if there are 2 part numbers used in 67 for the headlight switch.
Does anyone have a picture of a 1995149 headlight switch?

Merry Christmas to all.

[tom]

Don't have a 67, or an RS. As I stated, just a guess. This time a wrong guess. It's great to have folks like John on this site.
Merry Christmas

[BlackoutSteve]

Maybe someone with a 67 parts book could see if there are 2 part numbers used in 67 for the headlight switch.

Maybe someone can help me look it up. I have a 65-75 Chevrolet parts catalog and I'm looking in group 2.485 which is switches - lighting. I can't find any of these numbers.. Am I looking in the right place?
I just got the manual on pdf. It's huge and I don't know how to use it yet.

For example, it lists three 69 Camaro swtches though..
w/o RS, w/o console inst. cluster (U17) 1995175
w/RS, w/o console inst. cluster 1995176
w/o RS, w/console inst. cluster 1995177
w/RS, w/console inst. cluster combination not shown but w/o RS, w/console inst. cluster is listed twice. However, below this combo is 1995177 but U17 makes no mention of a different switch.

The 69 AIM lists 1995175 as non RS UPC12-B2
RS as 1995176 and RS w/U17 1995177. RPO Z22-B7. Same deal. A different switch for U17, but only with RS.
All this time, I also thought there was just two.

Confused? Me too..

[Mark]

Just to add a little more confusion the 69 Camaro Master Parts Manual from 1972 lists four switches for 69 Camaros.

1995173 - All exc RS - with console gauges
1995175 - All exc RS - exc console guages
1995176 - All with RS - exc console guages
1995177 - All with RS - with console guages

1995179 - 167 All, 1968 all exc RS, sup 1995164
1995167 - All with RS - type #D1574

The theory has always been that the dimmer on the RS switches had a higher power rating on it to account for the extra bulbs in the console guage housing.  I think I saw a picture of the two of them side by side and there was a size difference in the dimmer resistor but I don't have the picture on my PC.

[big iron]

You are looking in the correct group (2.485). The reason you can not find the service numbers I quoted is that they have been superseded in later parts books. That is the reason to try and use parts books that are printed for the model year in question.
A picture of the  67 (1995149 w/ U17) headlight switch would be greatly appreciated
Does anyone have a 67 parts book that would look up the two part numbers in question (1995147 & 1995149) and let us know what you find?

Maybe someone with a 67 parts book could see if there are 2 part numbers used in 67 for the headlight switch.

Maybe someone can help me look it up. I have a 65-75 Chevrolet parts catalog and I'm looking in group 2.485 which is switches - lighting. I can't find any of these numbers.. Am I looking in the right place?
I just got the manual on pdf. It's huge and I don't know how to use it yet.

For example, it lists three 69 Camaro swtches though..
w/o RS, w/o console inst. cluster (U17) 1995175
w/RS, w/o console inst. cluster 1995176
w/o RS, w/console inst. cluster 1995177
w/RS, w/console inst. cluster combination not shown but w/o RS, w/console inst. cluster is listed twice. However, below this combo is 1995177 but U17 makes no mention of a different switch.

The 69 AIM lists 1995175 as non RS UPC12-B2
RS as 1995176 and RS w/U17 1995177. RPO Z22-B7. Same deal. A different switch for U17, but only with RS.
All this time, I also thought there was just two.

Confused? Me too..

[Mark]

The 1995147 and 1995149 are production part numbers, not service part numbers.  There are two different numbering systems used by GM.  The engineering, or production part numbers are those parts made either by GM or by a subcontractor (like Delco) in accordance with design documents and installed on the vehicle in the assembly plant.  Service part numbers are for parts that may be exactly the same as the production part, or they may be a functionally acceptable part that will fit and function the same as the original but it may not look exactly the same.  The Service parts department can either keep the same part number or can assign new number if the original part number does not fit into their numbering system.  Initially the service department may carry both of these switches , or maybe they carried the RS switch but substituted one from a 66 or 67 Chevrolet for the other part since it was deemed to be funtionally identical.  A few years later they may consolidate those two switch part numbers down to just one, and a few years later just stop carrying the part all together.

[big iron]

Anyone with a 67 parts book?

[big iron]

Can someone with an original 67 w/gauges, be so kind, as to look at the bottom of the light switch and let us know the 3 numbers stamped in the metal cover?
Bob

Anyone with a 67 parts book?

[flyingskibiker]

Pretty interesting!  Does the '67 AIM call out a headlight switch in the U17 UPC?  The '68 Z22 does...

[big iron]

It calls for an 1995149 w/U17 gauges. The standard w/o gauges is 1995147. I believe that the 149 has a higher capacity dimmer sw. and if people are adding center consoles w/ gauges and do not upgrade their sw. there could be serious overheating problems.
I have not had a responce that might help answer the matter.
Bob

Pretty interesting!  Does the '67 AIM call out a headlight switch in the U17 UPC?  The '68 Z22 does...

[flyingskibiker]

Again, very interesting!  I guess if that is the case (higher capacity), the '68 was already that way.  So, no change for U17.  Changes along the way still happen even these days.  Just look at the electronic industry!  Good luck to you.  It's a tough road trying to figure this one out.
Chris B.

[big iron]

Chris,
JohnZ only indicated that the 149 sw. was changed to the 164 sw. in 68. He did not comment on what switches may have been used in 68, so 68 could also be a problem.
Also note Mark's responce that in 69  173 w/ gauges and 175 w/o gauges.
Mark,
My 67 sw. has the last three digits (147) of the part number stamped on the metal bottom, so I believe that the production number and the service number are the same in this case.
Bob

[My68SS]

It may be that the max resistance of the dimmer fitted is different depending on options and therefore the number of lamps [total current] it has to control, so the same dimming range is acheived.
Might be interesting for those with dimmers lying around and a good, accurate low ohms reading dmm to measure their dimmers along with what number it has stamped on it.

[flyingskibiker]

My ~11C '68 has 164 on the side.  Here to help... ;-)

[big iron]

Rob,
 I believe there is a physical difference in the size of the ceramic material that the dimmer w/gauges has that also allows for a higher wattage capacity in the dim position.
I have seen replacements that the dimmer section is 2x the size of the 147 that I have.
The 67 console w/gauges and 4 spd. have 5 additional lights and w/auto trans. 7. For the dimmer to dim the additional lights you would have to increase the dimmer resistance to drop more of the voltage at the dimmer.
There are 4 dash,2 court. and 1 dome ( 2 deluxe) = 8 lamps so you would need probably 2X the resistance of the 147 sw.
My original 147 shows 0 to 7 ohms across the resistor, measured with a Fluke 83. I used the # 3 trem. and the wiper for my measurement. I also tried term #2 and term#3 and could only get 0 to 6.3 ohms.
Bob

[big iron]

Does your build have a console w/ gauges?
Is it stamped on the plastic or the metal bottom?
Bob

My ~11C '68 has 164 on the side.  Here to help... ;-)

[flyingskibiker]

No idea if car came w/ gauges from the factory...  The car does have the tic-toc-tach and most wires match up w/ that (clock power w/ correct connector).  But the harness is pretty well hacked and unwrapped.  I haven't checked to see if the wires going to the aftermarket gauges are the correct color and go into the bundle of wires under there (gauges are mounted under the center of the dash where the U17s would be).  I will be doing that in the next couple months since I plan on replacing the harness and installing a console w/ gauges.  There IS the correct oil line hole in the firewall.  I did check that.  There is also a hole for the Muncie speed-o cable and jumper harness and hole for the back up lights.

If I look in the instrument cluster opening w/ them out of the car like they are now, I can look at the side of the switch and see it stamped into the metal near the rear of the switch.  It is not on the bottom as the switch is currently mounted.  The switch know release button is on the same side facing the cluster opening, as well.  I could take a picture pretty easily...

I bought an aftermarket switch.  I could easily measure the resistance on it.

[My68SS]

For the dimmer to dim the additional lights you would have to increase the dimmer resistance to drop more of the voltage at the dimmer.
Bob

Hi Bob,
It will be the other way round - more lamps = lower dimmer resistance.
e.g. For a given dimmer position/resistance, as you clip more lamps in parallel, the brightness of any one lamp decreases, as more voltage is dropped across the dimmer.

[Mark]

The resistance of the dimmer is fixed, its the wattage of the resistor that increases.  As you add more bulbs in parallel the circuit resistance gets lower, but the resistance thru any one bulb remains the same.

[My68SS]

The resistance of the dimmer is fixed, its the wattage of the resistor that increases.  As you add more bulbs in parallel the circuit resistance gets lower, but the resistance thru any one bulb remains the same.

That's true, more watts will be dissipated in the dimmer as you add more lamps. I was only wondering if they also changed the resistance of the dimmer to keep the same dimming range.
It may well be that this was considered of minor consequence and only the wattage of the dimmer was considered.

Having said that though, to some extent the two would go hand in hand anyway, higher wattage capability = heavier wire = lower resistance anyway [for roughly similar wire lengths]

[big iron]

Does anyone know why there are 2 67 headlight switches. Std.1995147 and 1995149 w/U17. Does the 149 have a higher rated light dimmer for the console ? See VPC 12 B6 and revision 4.
Anyone have an answer ?

[His67PC]

Attached are some pictures of 147 and 149 switches from cars I parted in the 70s.  Other than the dimmer switch blocks at the front of the switch, they look the same.  The 149 switch is the lighter colored dimmer.  There are some minor configuration differences in the dimmer block and the dimmer dial on the shaft is different.  I don't know know which pins to measure for resistance to tell the difference.  They may not be good as the dimmer was a common failure mode for these switches.

[His67PC]

A couple more shots:

[His67PC]

And...

[big iron]

Thanks for the reply His67PC,
Your picture of the 149 switch tells the whole story about the 67 option RPO U17.
Bob