Over the past 3 weeks I have attempted to get it working to no avail.


The boost gauge on my 87' 951 I just bought still doesn't work.

When I bought the car, I thought it was just a bad connection, but the previous owner gave me another KLR to put in to see if that helped fix the problem. The boost Gauge still doesn't work.

Then I thought it was just a bad connection. So I removed the instrument cluster and attempted to clean the connectors to insure a better connection. It still doesn't move the boost gauge.

The boost gauge DOES work, though. If you apply power directly to the gauge ( directly underneath the faceplate) the gauge moves... with varying power from the multimeter, I've been able to move it.

It just seems like a wiring problem then.. doesn't it?

Both the Shop manual and Haynes manual says its pins 1 & 2 that provide power to the gauge for it to work. Yet, when I apply power to pins 1 & 2, it doesn't move whatsoever. yet, when I apply power to pin #3 and put a positive connection to the gauge itself.. the gauge moves.


To compound the problem even further.. the shop manual says the wires should be BL & RT/GRN (black & red/green?) the Haynes Manual says they're red/green & Red/white.... the actualy #1&2 wires are white/blue and brown/blue ...

the next step of course is to wire a seperate wires to the KLR itself.. but which wires is the mystery since they're not the listed colors and I think the same colors are reused more than once.


this is just bewildering. I'd like to get my stock gauge working.


Any suggestions?

 

Adam,

I think it's a noble idea to keep the stock gauge working just to have all the original parts functioning, but most of the guys I've seen posting here (myself included) have installed a mechanical boost gauge to get our "real" measurements.

Sorry--I've never done any repairs on an electrical boost gauge like the factory one so I can't offer much help there, but for what it's worth, a decent mechanical gauge like a VDO only costs about $40.00.

Best Regards
Greg W.

 

Pin 5 on the KLR plug is for the intake vacuum signal (output for pressure display). Per the DME/KLr test manual. Check that wire.

 

Pin 5.. is that grounded to the chassis? Cause I get nothing if I ground it there.

what pin is the ground? I just put the dash back together and wanted to test it and make sure without tearing the dash apart again.

 

Update and Bump.

I stuck a wire in the KLR connector on Pin 5.... I'm able to get my multimeter needle to move. .but only with very small amounts of power... like 5-10 milivolts. Not enough to move the gauge.

but thats ONLY on pin 3... I thought pins 1 & 2 on connector B were the cuplrits.

I don't want to let something as silly as wiring stop this gauge from working.

anybody have ideas?

 

Pin map

 

Dme