Detail: On a 99 grand am the gas gauge allways reads empty what is the color is the ground wire for the gas gauge
Solution: It's not the ground wire , the gauge grounds inside the instrument cluster .Your sending unit or the gauge it's self is bad . Body Control System Operation The Body Control Module (BCM) performs the following functions: ?€¢ Gauge control ?€¢ Instrument cluster indicator control ?€¢ Fuel gauge control ?€¢ Temperature gauge control ?€¢ Theft deterrent ?€¢ A/C compressor request ?€¢ A/C cooling fan ?€¢ Exterior and interior lighting control for the following lamps: - Daytime Running Lights (DRL) - Automatic lighting control - Fog lamps - Interior lighting ?€¢ Battery rundown ?€¢ Chime Gauge Control The Body Control Module (BCM) receives Class 2 serial data messages from the Powertrain Control Module (PCM) to determine the following gauge information: ?€¢ Engine coolant temperature ?€¢ Fuel level sensing Your best bet is to take your vehicle to a qualified repair shop ! Fuel Gage Inaccurate or Inoperative Install a scan tool. Turn ON the ignition, with the engine OFF. Select the PCM display DTCs function on the scan tool. Does the scan tool display any DTCs? -- YES - Go to Diagnostic Trouble Code (DTC) List (2.4L) or Diagnostic Trouble Code (DTC) List (3.4L) in Engine Controls NO - Go to Step 3 3 With the scan tool, select Instrument Panel Cluster, Special Functions and command the fuel gauge UP. Does the fuel gauge complete a full sweep when commanded? -- YES - Go to Step 4 NO - Go to Step 12 Turn OFF the ignition. Disconnect the fuel level sender. Connect the J 33431-C Signal Generator and Instrument Panel Tester between the signal circuit of the fuel level sender and the ground circuit of the fuel level sender. Turn ON the ignition, with the engine OFF. Important: Verify the J 33431-C resistance setting with a DMM. Set the resistance on the J 33431-C to 40 ohms. Does the fuel gauge display at or below empty? -- YES - Go to Step 5 NO - Go to Step 6 , Hi, a 6ya Mechanic can help you resolve that issue over the phone in a minute or two. Best thing about this new service is that you are never placed on hold and get to talk to real repair professionals here in the US. click here to Talk to a Mechanic (only for users in the US for now) and get all the help you need. Goodluck! , The float that moves the gas hand is possibly stuck in the tank. If there's isn't an access hole in the rear of the vehicle you'll have to drop the tank. Unless it becomes free on it's own. Hope this is helpful. Please rate. Thanks , I have the same problem on my 99 ZR2 Blazer. This is the rheostat in the gas tank. I bought my part in Ebay for $27. The only issue is that you have to drop the gas tank and pull the sending unit to install. Hope this helps, I hear from other message boards that it is a very common problem in these vehicles. , Usually if the gas gage does not work yes it is true it may be the sensor if it is electronicly controlled. the sncor will more than likley be in the tank. here is how to remove your gas tank. Before servicing the vehicle, refer to the precautions section. Relieve fuel system pressure. Drain the fuel tank. Remove or disconnect the following: Negative battery cable Fuel filler and vent hoses Fuel tank skid plate Fuel tank wiring connectors Fuel supply and return lines Fuel tank Fuel pump assembly Fuel pump assembly mounting To install: Install or connect the following: Fuel pump assembly Fuel tank. Tighten the bolts to 27 ft. lbs. (36 Nm). Fuel supply and return lines Fuel tank wiring connectors Fuel tank skid plate Fuel filler and vent hoses Negative battery cable Start the engine and check for leaks. , Fuel level sending units are known to go bad on these. , you are going to have to replace the sending unit for the gas gauge, it is located in the fuel tank.