Steering Wheel & Steering Column: Diagnosis Chevrolet Uplander I

Diagnostic Starting Point - Steering Wheel Controls

Begin the system diagnosis with Diagnostic System Check - Vehicle . The Diagnostic System Check - Vehicle will provide the following information

1. The identification of the control modules which command the system
2. The ability of the control modules to communicate through the serial data circuit
3. The identification of any stored diagnostic trouble codes (DTCs) and their status

The use of the Diagnostic System Check - Vehicle will identify the correct procedure for diagnosing the system and where the procedure is located.

Diagnostic Fault Information

Diagnostic Aids

1. Before diagnosis of the steering wheel controls, ensure the primary controls of the associated component are functioning properly.
2. Review schematic when testing switch resistance values.

Circuit/System Testing

Note: It is Recommend that Component Testing be performed before Circuit Testing when diagnosing steering wheel controls.

1. Ignition OFF, disconnect the harness connector at the steering wheel control switches.
2. Ignition ON, Radio ON, test for 9.5-10.4 volts between the voltage circuit and ground at the right switch harness connector. If less than 9.5 volts test the voltage circuit for short to ground or open/high resistance. If circuit test normal, replace the radio. If greater than 10.4 volts, test the supply voltage circuit for short to voltage. If circuit test normal, replace the radio.
3. Ignition OFF, Install a 3-amp fused jumper wire in the right switch harness connector, between the voltage circuit and the voltage supply circuit to the left switch harness connector.
4. Ignition ON, Radio ON, test for 9.5-10.4 volts between the voltage circuit and ground at the left switch harness connector. If less than 9.5 volts, repair the voltage supply circuit for short to ground or open/high resistance between the left and right switch harness connectors.
5. Ignition ON, Radio ON, connect a test lamp between the signal circuits to the radio and ground at the left and right switch connectors. Verify lamp does not illuminate. If test lamp illuminates, test the signal circuits for short to voltage. If circuit test normal, replace the radio.
6. Ignition OFF, test for less than 1.0 ohm of resistance between the signal circuits to the radio and ground, at the left and right switch connectors. If greater than 1.0 ohm, test the signal circuits for open/high resistance. If circuit test normal, replace the radio.
7. Ignition OFF, disconnect the harness connector at the radio and switches, test for infinite resistance between the signal circuit and ground at the radio harness connector. If less than infinite resistance, test the signal circuit for short to ground.
8. If circuit test normal, test or replace switch.

Component Testing

1. Ignition OFF, disconnect the harness connector at the steering wheel control switches.
2. Test for infinite resistance between the supply voltage terminal and the signal terminal with the switch in the open position. If less than infinite resistance, replace the switch.
3. Test resistance values between the supply voltage terminal and the signal terminal with the switch closed in each position and verify readings are approximate to what the schematic reads. If values do not, replace the switch.

Visual/Physical Inspection

1. Inspect for aftermarket devices which could affect the operation of the steering wheel and column.
2. Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.

Symptoms List

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

1. «Steering Column Tilt Function Inoperative»(ref-241676-S07065568392006081100000)
2. «Lock System Does Not Unlock»(ref-241676-S27513669962006081100000)
3. «Lock System Does Not Lock»(ref-241676-S35844768332006081100000)
4. «Lock System Sticks in Start»(ref-241676-S42148491062006081100000)
5. «Ignition Key Cannot Be Removed from the Ignition Lock Cylinder»(ref-241676-S38547823492006081100000)
6. «Ignition Key Cannot Turn or Sticks in Any Position»(ref-241676-S37435675352006081100000)
7. «Noise in Steering Column»(ref-241676-S40396177282006081100000)
8. «High Shift Effort»(ref-241676-S29575953712006081100000)
9. «Looseness in Steering Column»(ref-241676-S26527176022006081100000)

Symptoms - Steering Wheel Controls

1. Inspect for aftermarket devices which may affect the operation of the Steering Wheel Controls System. Refer to «Checking Aftermarket Accessories»(ref-241671-S33907418562006081100000) .
2. Inspect for easily accessible or visible system components for obvious damage or conditions which may cause the symptom.

Symptom List

Refer to Steering Wheel Controls Inoperative in order to diagnose the symptom.

Inspection Procedure

1. Inspect the capsules on the steering column bracket assembly. Verify that the capsules are seated securely in the bracket slots and inspect the capsules for any loose conditions when pushed or pulled by hand. If the capsules are not secure, perform one of the following procedures: If the bracket is bolted to the jacket assembly, replace the bracket. If the bracket is welded to the jacket assembly, replace the jacket assembly.
2. Inspect the jacket assembly for collapse by measuring the distance from the lower edge of the upper jacket to a defined point on the lower jacket. If measured dimensions (A), are not within specifications (100 mm), install a steering column.