Boost gauge Actuator testing?

[sinannasirli]

Hi All,

My boost gauge was reading zero. I did clean the wires and repositioned them behind the gauge and it shows full scale deflection

As advised 9/10 to check the boost gauge activator ground, I have already done that.

The ground wire is connected to a good ground and also using a multimeter, gauge bracket and the other end of the black ground wire at the boost gauge has good contact only 1-2 ohms..

The same applies also for the light green wire.. So I can be sure that the leads go to the correct terminal.

Testing the boost gauge :

Between +(positive) and G(Gauge) terminal 135 ohm resistance

Between +(positive) to (-)Ground terminal 350 ohm resistance and 12 volts

Between -(Ground) to G(gauge terminal) 220 ohm resistance and (and 7,7 volts when ignition on)


So it looks like the gauge is working.. Normal circumstances it shows full scale deflection when ignition on.
If I swap the Gauge and Ground Cables it shows 0. (there is about 1 mm needle movement when the ignition is on, I only tried this to make sure that the usual non reading would occur when wires are reversed)

Boost Gauge Transducer:

This should act up as a resistance right? So I should assume there should be connectivity between the Ground (bracket) and the Gauge terminals with variable resistance depending on the pressure and logically more resistance the more the pressure is? As with gauge unplugged full scale deflection(high resistance), and if the gauge is shorted to ground zero gauge reading(less resistance)?

When I measure those two terminals there is no connectivity. Unlimited resistance.. Can any of you measure your working unit to confirm that it should be some connectivity? (What is that other WK terminal btw?)

Can I assume the transducer is at fault? Is there a way to check further? I tried to open it up but it looks like a sealed unit.

Any help appreciated..

Regards

Sinan

[sinannasirli]

So apparently tried with a friends car. My gauge works but the transducer is at fault...

So if someone wants to troubleshoot for a similar situation:

Measuring Resistance for Boost Gauge Testing (Disconnect all Wires before testing)

+ and G terminal : 130 ohms..

- and G terminal : 220 ohms

- and + Terminal : 350 ohms

Measuring Resistance for Boost Gauge Transducer Testing:(Disconnect green wire (G terminal before testing)

Resistance between G Terminal and Transducer Ground (Bracket) : about 15 ohms...

I would say it might vary by 10%, but anything majorly different would indicate a faulty gauge/transducer...


This info you might want to put to WikiLec..
Regards

Sinan