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Discussion Starter · #1 ·
The entire time i have had my rodeo the fuel gauge has not worked and i cannot figure out why ive done all i know to do so i was wondering how difficult wiring up an aftermarket fuel gauge would be and if anyone had recommendations for what type or what specific gauge i should use. Thanks.
 

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Are you talking about a standalone gauge, or about one that fits in the cluster?
 

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There is only one wire connecting the 01 Rodeo fuel gauge to the Powertrain Control Module (PCM) and two wires connecting the fuel tank fuel level potentiometer to the PCM.
The resistance of the potentiometer is 80 ohms to 290 ohms.

PCM E-22 Pin 50 Orange/Green fuel level potentiometer signal
PCM E-22 Pin 60 Blue/Yellow fuel level potentiometer ground
PCM E-22 Pin 48 Yellow/Red to instrument panel connector I-9 Pin 3

The Fuel Level Gauge has 3 connections:
The fuel level signal from the PCM via instrument panel connector I-9 Pin 3
The fuel level gauge ground, shared with the other gauges
The fuel level gauge +12 Vdc power, shared with the other gauges

If your Fuel Level Gauge does not work there is likely a broken wire between the PCM and the fuel tank connector or a defective fuel level potentiometer.

It is easier to fix your truck than trying to retrofit an aftermarket gauge imho.
 

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Discussion Starter · #5 ·
There is only one wire connecting the 01 Rodeo fuel gauge to the Powertrain Control Module (PCM) and two wires connecting the fuel tank fuel level potentiometer to the PCM.
The resistance of the potentiometer is 80 ohms to 290 ohms.

PCM E-22 Pin 50 Orange/Green fuel level potentiometer signal
PCM E-22 Pin 60 Blue/Yellow fuel level potentiometer ground
PCM E-22 Pin 48 Yellow/Red to instrument panel connector I-9 Pin 3

The Fuel Level Gauge has 3 connections:
The fuel level signal from the PCM via instrument panel connector I-9 Pin 3
The fuel level gauge ground, shared with the other gauges
The fuel level gauge +12 Vdc power, shared with the other gauges

If your Fuel Level Gauge does not work there is likely a broken wire between the PCM and the fuel tank connector or a defective fuel level potentiometer.

It is easier to fix your truck than trying to retrofit an aftermarket gauge imho.
I have already had the fuel level potentiometer replaced and that didnt fix the problem and its weird like if i hit a bump or something the gauge might work for a minute but its very rare that this happens so im noy sure where to look really to fix this
 

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This is the schematic, break out your ohm meter and look for the open circuit. Click on schematic to expand.
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One more question it is also throwing the code P0463 - Fuel level sensor A circuit high input does that narrow anything down
Does the the gauge show Full Or Empty Or some other value?
 

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The fuel level sending unit is a variable resistor called a potentiometer. The potentiometer is controlled by a float that moves up or down depending on the fuel level in the tank. The potentiometer has an operating range of 80 ohms to 290 ohms, 80 ohms when the tank is full to 290 ohms when the tank is empty. There are two wires connected to the potentiometer, one is a +5 volt direct current (Vdc) source provided by the Powertrain Control Unit (PCM) and the other is a signal ground, also connected to the PCM. As the resistance of the potentiometer changes the electrical current flow in the circuit changes. If there is no current flow because the circuit is open (broken wire) the voltage at the PCM input sensor remains at +5Vdc. The PCM will detect this and set DTC P0463.

The two wires from the potentiometer are connected to the PCM using five electrical connectors.
Fuel Pump assembly at the fuel tank (F-1)
PCM (E-22)
H-5 is a 16 Pin Green Connector on the LH inner fender.
H-15 is 20 Pin Blue Connector behind the LH kick panel
H-25 is a 13 Pin White Connector under the LH (driver) seat

See if you can locate the H-15 connector.
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Discussion Starter · #12 ·
The fuel level sending unit is a variable resistor called a potentiometer. The potentiometer is controlled by a float that moves up or down depending on the fuel level in the tank. The potentiometer has an operating range of 80 ohms to 290 ohms, 80 ohms when the tank is full to 290 ohms when the tank is empty. There are two wires connected to the potentiometer, one is a +5 volt direct current (Vdc) source provided by the Powertrain Control Unit (PCM) and the other is a signal ground, also connected to the PCM. As the resistance of the potentiometer changes the electrical current flow in the circuit changes. If there is no current flow because the circuit is open (broken wire) the voltage at the PCM input sensor remains at +5Vdc. The PCM will detect this and set DTC P0463.

The two wires from the potentiometer are connected to the PCM using five electrical connectors.
Fuel Pump assembly at the fuel tank (F-1)
PCM (E-22)
H-5 is a 16 Pin Green Connector on the LH inner fender.
H-15 is 20 Pin Blue Connector behind the LH kick panel
H-25 is a 13 Pin White Connector under the LH (driver) seat

See if you can locate the H-15 connector.
View attachment 120201
Yes i found it now what?
 

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The image shows the H-15 connector faces, one face with pins and other with sockets. You can't tell from the image which side has the pins or which side has the sockets. So I refer to the wire position in the connector as a hole.

H-15 hole 11 contains a Blue/Yellow wire and hole 17 contains a Orange/Green wire. These two wires are connected to the fuel level potentiometer on one half of H-15 and the PCM on other half of H-15 . One half of H-15 has hole 11 and hole 17 wires that go to a connector under the driver seat, these connect to the fuel level potentiometer.

Separate the H-15 connector and measure the resistance between hole 11 and 17 on the connector half that has the Blue/Yellow and Orange/Green wires connected to the connector under the seat.

Since the fuel level potentiometer range is 80 to 290 ohms the expected measured resistance should be in this range. However, I think your going to read infinity because I expect one of these wires is open ("broken") between H-15 and the fuel tank. The next step depends on the results of this test. It is a good idea to disconnect the battery before separating the H-15 connector faces and running the resistance test.
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Discussion Starter · #14 · (Edited)
The image shows the H-15 connector faces, one face with pins and other with sockets. You can't tell from the image which side has the pins or which side has the sockets. So I refer to the wire position in the connector as a hole.

H-15 hole 11 contains a Blue/Yellow wire and hole 17 contains a Orange/Green wire. These two wires are connected to the fuel level potentiometer on one half of H-15 and the PCM on other half of H-15 . One half of H-15 has hole 11 and hole 17 wires that go to a connector under the driver seat, these connect to the fuel level potentiometer.

Separate the H-15 connector and measure the resistance between hole 11 and 17 on the connector half that has the Blue/Yellow and Orange/Green wires connected to the connector under the seat.

Since the fuel level potentiometer range is 80 to 290 ohms the expected measured resistance should be in this range. However, I think your going to read infinity because I expect one of these wires is open ("broken") between H-15 and the fuel tank. The next step depends on the results of this test. It is a good idea to disconnect the battery before separating the H-15 connector faces and running the resistance test. View attachment 120214
So my meter is a little old so idk about infinity but when i tried to test it all it did was not change at all
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I also tested them at the connector under the seat and got the same thing
 

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What does the meter indicate when you touch the leads together on the 2000 ohms scale?
What does the meter indicate when the leads are not touching each other on the 2000 ohms scale?
 

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Discussion Starter · #16 ·
What does the meter indicate when you touch the leads together on the 2000 ohms scale?
What does the meter indicate when the leads are not touching each other on the 2000 ohms scale?
When the leads are not touching it indicates the same as i got when from the picture before and when they are touching it reads either 000 or 001
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If your reading across the correct connector locations, your meter is indicating that the fuel level potentiometer is not connected which is why the gauge does not work. You will have to access the connector on the fuel pump assembly and continuity check each wire from the H-15 (or under seat connector) to the pump assembly connector and figure out which wire is open and repair it.
 

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Discussion Starter · #18 ·
If your reading across the correct connector locations, your meter is indicating that the fuel level potentiometer is not connected which is why the gauge does not work. You will have to access the connector on the fuel pump assembly and continuity check each wire from the H-15 (or under seat connector) to the pump assembly connector and figure out which wire is open and repair it.
Okay thank you so much, i just filled up not long ago so ill have to wait until im low on gas and drop the tank. I hope i can find it and get it fixed but you have been such a great help i cant thank you enough weve wasted hundreds across 2 repair shops trying to get it fixed and this is the closest ive been in the past year.
 
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