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Lou P.
Lou P., ASE Certified Technician
Category: GM
Satisfied Customers: 3727
Experience:  I Have knowledge in almost all car lines and can help with general questions and more!!!!!
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I have a 2004 gmc savanna cargo 2500 And my instrument

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I have a 2004 gmc savanna cargo 2500
And my instrument cluster some of the gauges are not functioning
I replaced the cluster with a new one but the same two gauges do not work
Fuel gauge and oil pressure gauge and I don't see anything helpful in the Haynes repair manual
Any help on what I should and could check would be greatly appreciated thank you

Hello, so when you say you replaced with a new one do you mean new from dealer or just new as in replaced like from a junk yard or used car?

also when you start the van do all the gauges do the test sweep ?

Customer: replied 5 months ago.
They all flicker downward but none of them run through or do a full sweep over gauge numbers if this what you mean
Cluster I purchased on eBay as factory oem replacement I believe it a delco part

ok, the gauges should all sweep from the bottom reading to the top reading when the key is turned on, so that is odd, but lets see what we can do to make sure the cluster is not the issue, do you know how to test wiring by checking volts, ohms, continuity?

Customer: replied 5 months ago.

ok good deal, so we need to access the oil pressure sensor and connector on the engine we will start with that one there.

what engine is in your model?

Customer: replied 5 months ago.
4.8

ok thanks, ***** ***** have a 3 pin oil pressure sensor connector.

behind the distributor , so the dog house will need to be removed. ill tell you what we need to do once that is accessed

connector pinout

here is the oil pressure switch wiring, we need to verify power and ground at the connector and then we can cross wires to see if we can influence the gauge.

then we can check the fuel level as well. same way

Customer: replied 5 months ago.
Ok would u be able to most likely find the parts and connectors in a Haynes repair manual ? If so under what section

well i sent you links to the wiring did you not see them?

Customer: replied 5 months ago.
I see them but I'm just not sure where to find all these connectors ? That I need to test , are they behind the cluster in the fuse box next to or connected to the oil pressure switch and fuel pump ?

oh ok, first we will access the oil pressure switch , it is located under the distributor at the back of the engine, so you will have to remove the dog house or engine cover what have you.

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