I have a 2000 Suburban LS 1500 with a 5.3 and about 6 months ago my gas gauge just stopped working, therefore I assumed it was the fuel level sensor in the sending unit. After spending a ton of time replacing it last night the end result is still a broken gauge. The fuel pump itself functions just fine but I cannot figure out why the gauge isn't working. Doing a bit of searching online it would either have to do with a bad ground or possibly the cluster itself.

I checked all of the grounds to the body that come from the wiring harness on the fuel pump, I believe there were a total of two and they all look fine. Then the harness goes up into firewall area to the computer. I am not sure exactly what I should test to find out if it's the gauge or the wiring but I was told I could check the resistance across the two wires or the signal coming into the gauge. I know there isn't a gas gauge fuse so just looking for some information here.

I have been using the trip gauge for my mileage and looks like the gas gauge failure is a common problem on these GM Trucks.

Thanks.

 

Grab a cluster from ebay and you'll be good to go. Your only other option is to have access to a tech 2 log into the IPC and verify what readings the cluster is actually seeing from the pcm.

 

The cluster gets the fuel level off of the serial buss there are no direct wiring connections to the cluster. The sender wiring goes to the pcm and is processed then broadcast over the buss to the cluster.

 

The cluster gets the fuel level off of the serial buss there are no direct wiring connections to the cluster. The sender wiring goes to the pcm and is processed then broadcast over the buss to the cluster.

 

Hmm I did not know this. Replacing the cluster though will jack up the mileage reading and so forth correct? Isn't there a way to tell if the sensor is actually picking up a reading though just to be 100% sure.

 

Yea with a scan tool. You can also do a gauge sweep with the scan tool to show if the gauge is dead. If you get a dorman cluster, you fill out a form and it is programmed with your mileage, hours, etc. Ive also heard you can just buy the gauge stepper motors off of ebay if your electronics savy.

 

You can have someone with HPTuners or EFILive can scan the fuel level.

 

Get the cluster calibrated when you purchase. I think PCMcalibrators or whatever his name was sells clusters on here.

If you want, you can test the resistance of the fuel level sender with a multimeter to see if it is really working.

 

If it makes any difference the Low Fuel light is on. I will look at these charts too. When I asked someone about repairs they asked if the low fuel light was on. Thanks.

 

Thanks for all the help. A few people who rebuild clusters told me that if the low fuel light is on then there is a problem not related to the cluster itself. It takes less than 0.9v to set the low fuel light on, therefore the signal is not coming from the sensor into the cluster or pcm for that matter. It is either a bad ground or some wiring issue somewhere. I will try to get a good schematic to go by.