Printable Version of Topic

Click here to view this topic in its original format

914World.com _ 914World Garage _ Combo Gauge Wiring

Posted by: gfg3 Jan 30 2017, 10:43 AM

I've spent the past several days trying to find a picture of the back of my combo gauge showing the wiring (or a wiring diagram). I have various current flow diagrams and I've found the info for lots of other 914 combo gauges but not for this one (part # 914-641-101-50).

Attached Image

According to the Parts Vault (thanks for the picture - better than I could have done) this gauge was for 74, 75, 76 914/4 2.0 cars which came without a center console. It's mounted on the left side of my dash. Not working properly, but just in case the PO fiddled with it, I'd like to see how it's supposed to be wired before I dive into it.

I'm not an electrical expert, so simpler is better. Can anyone help? Thanks.

George


Posted by: JFG Jan 30 2017, 12:10 PM

http://forums.pelicanparts.com/porsche-914-914-6-technical-forum/501595-can-anyone-post-up-wiring-back-gauges-where-goes.html

is this any good? i'm not good at electricals either so hope it helps

Posted by: JFG Jan 30 2017, 12:15 PM

[attachmentid=591263]

or this?

Posted by: gfg3 Jan 30 2017, 12:54 PM

QUOTE(JFG @ Jan 30 2017, 01:10 PM) *

is this any good? i'm not good at electricals either so hope it helps


Saw this post, but this is different combo gauge. Good info in the posts about wire colors, but I'd sure like to see how it all hooks up to my gauge. Thanks anyway.

George

Posted by: StratPlayer Jan 30 2017, 01:02 PM

Hope this helps


Attached image(s)
Attached Image

Posted by: gfg3 Jan 30 2017, 01:09 PM

QUOTE(StratPlayer @ Jan 30 2017, 02:02 PM) *

Hope this helps

This looks like it. Thanks much! If I run into more difficulties once I pull the gauge I'll be sure to ask again. Love this site!

George

Posted by: bandjoey Jan 30 2017, 01:18 PM

Or this too
As I was told the temp part requires power, ground, and the wire from the taco plate.

http://www.p914.com/p914_gauges_fuel.htm

Posted by: gfg3 Jan 30 2017, 01:48 PM

QUOTE(bandjoey @ Jan 30 2017, 02:18 PM) *

Or this too
As I was told the temp part requires power, ground, and the wire from the taco plate.


Thanks! I think that between your info here, the drawing that StratPlayer posted and the info in some of the earlier posts, I should be able to reconstruct "truth". If I come up with a workable drawing I'll post it to get comments.

George

Posted by: JFG Jan 30 2017, 02:40 PM

I'm going to need that drawing for deconstructing the birds nest that is my cabin wiring loom. Thanks

Posted by: gfg3 Jan 31 2017, 03:39 PM

QUOTE(JFG @ Jan 30 2017, 03:40 PM) *

I'm going to need that drawing for deconstructing the birds nest that is my cabin wiring loom. Thanks


OK. Here's what I came up with for the alternative combo gauge for '74 and newer 2.0 cars without the center console. I used several current flow diagrams and photos of the back of an unwired gauge. No warranties expressed or implied. In fact, since I am not an electrical guru, I would welcome anyone who actually can read wiring diagrams to critique this. I think I got the wire colors and connections close to being right, but who knows? Also, all the red/white wires are the various switched power connections. I assume they come together somewhere. Oh, and I know that ground has its own special symbol, but I was too lazy to build it in Powerpoint.

Anyway, please....critique away.

George

Attached Image

Posted by: Edward Blume Oct 11 2017, 07:37 PM

QUOTE(StratPlayer @ Jan 30 2017, 12:02 PM) *

Hope this helps

Sorry for the hijack, but is there no black / blue wire necessary for this combo gauge? Its supposed to be the original background lamp, but the combo gauge doesn't seem to have it.

Posted by: Larmo63 Oct 11 2017, 07:47 PM

All gauge lights are black w/blue tracer....

Right?

Btw, where does one source the teeny bulbs for the center heater control sliders?









Posted by: Edward Blume Oct 12 2017, 05:43 AM

QUOTE(Larmo63 @ Oct 11 2017, 06:47 PM) *

All gauge lights are black w/blue tracer....

Right?

Btw, where does one source the teeny bulbs for the center heater control sliders?


Yes, the black with blue tracer is in the Bowlsby original diagram, but the combo gauge above doesn't have it. is this correct?

Posted by: worn Oct 12 2017, 09:25 AM

Sort of on topic - the alternator needs the correct GEN warning light bulb to function. If you are tempted to go all LED while you are there, don't use one for that warning light.

Posted by: Edward Blume Oct 12 2017, 10:28 AM

Here's the Bowlsby diagram. The black with blue wire is present on stock, but not on the combo gauge. Correct? Do I just tape it off?


Attached image(s)
Attached Image

Posted by: Jonathan Livesay Oct 12 2017, 11:05 AM

QUOTE(gfg3 @ Jan 31 2017, 02:39 PM) *

QUOTE(JFG @ Jan 30 2017, 03:40 PM) *

I'm going to need that drawing for deconstructing the birds nest that is my cabin wiring loom. Thanks


OK. Here's what I came up with for the alternative combo gauge for '74 and newer 2.0 cars without the center console. I used several current flow diagrams and photos of the back of an unwired gauge. No warranties expressed or implied. In fact, since I am not an electrical guru, I would welcome anyone who actually can read wiring diagrams to critique this. I think I got the wire colors and connections close to being right, but who knows? Also, all the red/white wires are the various switched power connections. I assume they come together somewhere. Oh, and I know that ground has its own special symbol, but I was too lazy to build it in Powerpoint.

Anyway, please....critique away.

George

Attached Image

The black/purple wire goes to the bulb next to the oil pressure light and lights the gauge. Where the circle with the X in it is in the diagram.

Posted by: timothy_nd28 Oct 12 2017, 11:13 AM

If you put the black/purple wire on a lamp, the engine will cease to run

Posted by: Edward Blume Oct 12 2017, 11:35 AM

QUOTE(timothy_nd28 @ Oct 12 2017, 10:13 AM) *

If you put the black/purple wire on a lamp, the engine will cease to run

Are you answering the prior post? Where the X goes?

I agree that the X misses the mark. If you look in post 1 here, its an amber warning light.

Bowlsby's diagram lists it as gauge lighting. #1

Posted by: Jonathan Livesay Oct 12 2017, 12:05 PM

QUOTE(Edward Blume @ Oct 12 2017, 10:35 AM) *

QUOTE(timothy_nd28 @ Oct 12 2017, 10:13 AM) *

If you put the black/purple wire on a lamp, the engine will cease to run

Are you answering the prior post? Where the X goes?

I agree that the X misses the mark. If you look in post 1 here, its an amber warning light.

Bowlsby's diagram lists it as gauge lighting. #1

The off white dot is just for looks, no light goes through it, the bulb in that space lights both the gas and temp. gauges.

Posted by: Jonathan Livesay Oct 12 2017, 12:17 PM

QUOTE(timothy_nd28 @ Oct 12 2017, 10:13 AM) *

If you put the black/purple wire on a lamp, the engine will cease to run

Yeah, oops I meant to say black and blue wire, does that make more sense? dry.gif

Posted by: GregAmy Oct 12 2017, 12:35 PM

Not sure what you're trying to do, but here's some photos from a pair of combo gauges I have/had for sale in the Classifieds.

Combo on left is a 914.641.101.50. Per P914, this is from "1974-1976 2.0L models in which the "Appearance Group" was not ordered, making them rare, but more common than the 1973 combo gauges." I bought this one when I removed my center console in my '74.

However, earlier this year I bought off eBay the right combo. That's 914.641.102.40. Per P914 this is "the 1973 and very early 1974 model year Porsche 914 fuel gauge". It's slightly dented at around 2 o'clock.

HOWEVER, I've swapped the fuel gauges, because the one in my .50 stopped working. So to get the correct holes/plugs, mentally swap the fuel gauge from the right side into the left side.

Does this help?

All that said...what are you trying to do? Just identify which wire goes where?


[attachmentid=623090][attachmentid=623091]Attached Image Attached Image

Posted by: Edward Blume Oct 12 2017, 01:10 PM

Cool. So the black / blue wire is listed on the original dummy gauge as lighting the gauge cluster (Bowlsby diagram #1), the combo gauge has no place for it, at least listed on the diagram above.

Posted by: Jonathan Livesay Oct 12 2017, 01:43 PM

QUOTE(Edward Blume @ Oct 12 2017, 12:10 PM) *

Cool. So the black / blue wire is listed on the original dummy gauge as lighting the gauge cluster (Bowlsby diagram #1), the combo gauge has no place for it, at least listed on the diagram above.

The combo gas/temp gauge does have a place for a gauge light it is the opening for a bulb socket that is behind the off white or beige dot right next to the green oil pressure warning dot. It is actually in the same position as the gauge light on the gauge without temp. gauge. All the lights are the same they just moved the brake warning light from the top position (replaced by the temp gauge) to the left of the generator light.

Posted by: JFG Oct 12 2017, 02:03 PM

I have this gauge too. My white light was a blistered orange colour with no bulb holder fitted, so i replaced it with an orange semi transparent sticker and blanked the back of it. Going to have to revisit this.

Posted by: Jonathan Livesay Oct 12 2017, 02:26 PM

IPB Image
This is what you should see if you pull one of the gauges off, three rubber shrouds that direct light to the warning lights and one reflector to back light the gauges.

Powered by Invision Power Board (http://www.invisionboard.com)
© Invision Power Services (http://www.invisionpower.com)