Chevrolet Silverado / GMC Sierra. Manual — part 2428

If less than the specified range, test the secondary signal circuit for a short to voltage
or an open/high resistance. If the circuit tests normal, replace the ECM.

4. If all circuits test normal, test or replace the secondary fuel level sensor.

Component Testing

1. Ignition OFF, remove the secondary fuel level sender.

2. While sweeping the fuel level sensor through its full range of motion, test for a minimum

resistance value of less than 41 ohms and a maximum value greater than 119 ohms between
the secondary signal terminal B and the low reference terminal C.

If not within the specified range, replace the secondary fuel level sensor.

Repair Procedures

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Fuel Level Sensor Replacement (Extended Cab w/26 Gal Tank) or Fuel Level Sensor
Replacement (Regular Cab w/34 Gal Tank) or Fuel Level Sensor Replacement
(Regular Cab w/26 Gal Tank) for the 4.3L engine

Fuel Level Sensor Replacement (15 Reg Cab w/26 gal Tank) or Fuel Level Sensor
Replacement (15 Ext/Crew Cab w/26 gal Tank) or Fuel Level Sensor Replacement
(25 Ext/Crew Cab w/26 gal Tank) or Fuel Level Sensor Replacement (15/25
Reg/Ext/Crew Cab w/34 gal Tank) or Fuel Level Sensor Replacement (35
Reg/Ext/Crew Cab w/34 gal Tank) for the 4.8L, 5.3L, 6.0L, and 6.2L engines

Fuel Level Sensor Replacement (Cab/Chassis - Rear Tank) for the 6.6L engine

Control Module References for ECM replacement, setup, and programming

SYMPTOMS - DISPLAYS AND GAGES

1. Perform the Diagnostic System Check - Vehicle , before using the Symptom Tables in

order to verify that all of the following are true:

There are no DTCs set.

The control modules can communicate via the serial data link.

2. Review the system operation in order to familiarize yourself with the system functions.

Refer to the following:

IMPORTANT: The following steps must be completed before using the symptom

tables.

2008 Chevrolet Silverado 1500

2008 ACCESSORIES & EQUIPMENT Displays and Gages - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &

Silverado

Instrument Cluster Description and Operation

Indicator/Warning Message Description and Operation

Driver Information Center (DIC) Description and Operation

Audible Warnings Description and Operation

Visual/Physical Inspection

Inspect for aftermarket devices which could affect the operation of the Instrument Cluster or
Audible Warning Systems. Refer to Checking Aftermarket Accessories .

Inspect the easily accessible or visible system components for obvious damage or conditions
which could cause the symptom.

Inspect for proper fluid level.

Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to
Testing for Intermittent Conditions and Poor Connections .

Symptom List

Refer to a symptom diagnostic procedure from the following list in order to diagnose the
symptom:

Gages and Odometer

Instrument Cluster Inoperative

Engine Coolant Temperature Gage Inaccurate or Inoperative

Fuel Gage Inaccurate or Inoperative (Single Tank) or Fuel Gage Inaccurate or
Inoperative (Dual Tank)

Hourmeter Inaccurate or Inoperative

Speedometer and/or Odometer Inaccurate or Inoperative

Tachometer Inaccurate or Inoperative

Volt Gage Inaccurate or Inoperative

Indicators

Compass Malfunction (Mirror)

Engine Oil Pressure Indicator Malfunction

2008 Chevrolet Silverado 1500

2008 ACCESSORIES & EQUIPMENT Displays and Gages - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &

Silverado

Door Ajar Indicator Malfunction (w/AN3) or Door Ajar Indicator Malfunction (w/o
AN3)

Four-Wheel Drive Indicator Always On for the MP 1222/1225/1226-NQG transfer case

Four-Wheel Drive Indicator Inoperative for the MP 1222/1225/1226-NQG transfer case

Transfer Case Shift Control Switch Inoperative for the MP 1625/1626-NQF transfer
case

Transfer Case Shift Control Switch Indicator Always On - Two or More for the MP
1625/1626-NQF transfer case

Transfer Case Shift Control Switch Indicator Inoperative - One or More for the MP
1625/1626-NQF transfer case

Service Indicator Always On for the MP 1625/1626-NQF transfer case

Transfer Case Shift Control Switch Indicator Always On - Two or More for the MP
3023/3024-NQH transfer case

Transfer Case Shift Control Switch Indicator Inoperative - One or More for the MP
3023/3024-NQH transfer case

Service Indicator Always On for the MP 3023/3024-NQH transfer case

Brake Warning Indicator Malfunction

ABS Indicator Malfunction

StabiliTrak Indicator Malfunction

Traction Off Indicator Malfunction

Charge Indicator Malfunction

Water-in-Fuel Lamp Always On

Malfunction Indicator Lamp (MIL) Diagnosis for the 4.3L engine

Malfunction Indicator Lamp (MIL) Diagnosis for the 4.8L, 5.3L, 6.0L, 6.2L, or 7.0L
engine

Malfunction Indicator Lamp (MIL) Diagnosis for the 6.6L (LMM) engine

Tow/Haul Switch/Indicator Always On or Inoperative for the 4L60-E/4L65-E/4L70-E
automatic transmission

Tow/Haul Switch/Indicator Always On or Inoperative for the 6L50/6L80/6L90
automatic transmission

Low Washer Fluid Indicator Malfunction

High Beam Indicator Malfunction

Turn Signal Lamps and/or Indicators Malfunction

2008 Chevrolet Silverado 1500

2008 ACCESSORIES & EQUIPMENT Displays and Gages - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &

Silverado