Skip to content
Tahoe / Yukon Service Manual

DTC C103C-C103F

Diagnostic Instructions Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Review Strategy Based Diagnosis for an overview of the diagnostic approach. Diagnostic Procedure Instructions provides an overview of each diagnostic category. DTC Descriptors DTC C103C Left Front Strut Position Sensor Signal DTC C103D Left Rear Strut Position Sensor Signal DTC C103E Right Front Strut Position Sensor Signal DTC C103F Right Rear Strut Position Sensor Signal For symptom byte information, refer to Symptom Byte List. Diagnostic Fault Information

Circuit Number Circuit Function Short to Ground Open/High Resistance Short to Voltage Signal Performan ce
1205 Voltage Reference C103C 11 C103C 15 C103C 12 –
1207 Signal C103C 11 C103C 15 C103C 12 C103C 28, C103C 64
1206 Low Reference – C103C 15 – –
1208 Voltage Reference C103D 11 C103D 15 C103D 12 –
1210 Signal C103D 11 C103D 15 C103D 12 C103D 28, C103D 64
1209 Low Reference – C103D 15 – –
1211 Voltage Reference C103E 11 C103E 15 C103E 12 –
1213 Signal C103E 11 C103E 15 C103E 12 C103E 28, C103E 64
1212 Low Reference – C103E 15 – –
Circuit Number Circuit Function Short to Ground Open/High Resistance Short to Voltage Signal Performan
1214 Voltage Reference C103F 11 C103F 15 C103F 12 –
1216 Signal C103F 11 C103F 15 C103F 12 C103C 28, C103C 64
1215 Low Reference – C103F 15 – –

Circuit/System Description The K5 Automatic Level Control Module supplies a 5 V reference signal to each B11 Suspension 4 Corner Leveling System Position Sensor. The B11 Suspension 4 Corner Leveling System Position Sensor supply a signal of 0.5–4.5 V to the K5 Automatic Level Control Module. The sensors are also grounded through the K5 Automatic Level Control Module. Conditions for Running the DTC Battery voltage is between 9–16 V. Ignition is ON. Conditions for Setting the DTC The K5 Automatic Level Control Module measures a B11 Suspension 4 Corner Leveling System Position Sensor signal less than 0.5 V or greater than 4.5 V for more than 1.5 s. Action Taken When the DTC Sets Single position sensor fault signal ignored, substituted with opposite axle. Dual position sensor fault system offline, Speed Limited. The K5 Automatic Level Control Module sends a message to the instrument panel cluster to display SERVICE LEVELING SYSTEM message. Conditions for Clearing the DTC A present DTC will clear on the next consecutive malfunction-free ignition cycle. A history DTC will clear after 40 consecutive malfunction-free ignition cycles. Reference Information Schematic Reference Electronic Suspension Control Schematics Connector End View Reference Master Electrical Component List Description and Operation Electronic Suspension Control Description and Operation Electrical Information Reference Circuit Testing Connector Repairs Testing for Intermittent Conditions and Poor Connections Wiring Repairs Scan Tool Reference Control Module References for scan tool information Circuit/System Verification

  1. Verify DTCs C103C 11, C103C 12, C103C 15, C103D 11, C103D 12, C103D 15, C103E 11, C103E 12, C103E 15, C103F 11, C103F 12 or C103F 15 are not set. ⇒ If any of the DTCs are set Refer to Circuit/System Testing: Test A ⇓ If DTCs are not set
  2. Verify DTCs C103C 64, C103D 64, C103E 64, or C103F 64 are not set. ⇒ If one of the DTCs are set Refer to Circuit/System Testing: Test B ⇓ If DTCs are not set
  3. Verify DTCs C103C 28, C103D 28, C103E 28, or C103F 28 are not set. ⇒ If one of the DTCs are set Refer to Circuit/System Testing: Test C ⇓ If DTCs are not set
  4. A fault is not currently present and may be an intermittent condition. Circuit/System Testing Test A
  5. Ignition OFF and all vehicle systems OFF. Disconnect the connector at the appropriate B11 Suspension 4 Corner Leveling System Position Sensor: DTC C103C = B11LF Front Suspension 4 Corner Leveling System Position Sensor — Left DTC C103D = B11LR Rear Suspension 4 Corner Leveling System Position Sensor — Left DTC C103E = B11RF Front Suspension 4 Corner Leveling System Position Sensor — Right DTC C103F = B11RR Rear Suspension 4 Corner Leveling System Position Sensor — Right
  6. Test for less than 10 Ω between the low reference circuit terminal 2 and ground. ⇒ If 10 Ω or greater 2.1. Test the appropriate circuit for an open/high resistance: DTC C103C = Circuit 1206 DTC C103D = Circuit 1209 DTC C103E = Circuit 1212 DTC C103F = Circuit 1215 ⇒ If an open/high resistance is found, repair the circuit fault. ⇓ If an open/high resistance is not found 2.2. Replace the K5 Automatic Level Control Module. ⇓ If less than 10 Ω
  7. Ignition ON.
  8. Test for 4.8–5.2 V between the 5 V reference circuit terminal 1 and ground. ⇒ If less than 4.8 V 4.1. Test the appropriate circuit for a short to ground: DTC C103C = Circuit 1205 DTC C103D = Circuit 1208 DTC C103E = Circuit 1211 DTC C103F = Circuit 1214 ⇒ If a short to ground is found, repair the circuit fault. ⇓ If a short to ground is not found 4.2. Test the appropriate circuit for an open/high resistance: DTC C103C = Circuit 1205 DTC C103D = Circuit 1208 DTC C103E = Circuit 1211 DTC C103F = Circuit 1214 ⇒ If an open/high resistance is found, repair the circuit fault. ⇓ If an open/high resistance is not found 4.3. Replace the K5 Automatic Level Control Module. ⇒ If greater than 5.2 V 4.1. Test the appropriate circuit for a short to voltage: DTC C103C = Circuit 1205 DTC C103D = Circuit 1208 DTC C103E = Circuit 1211 DTC C103F = Circuit 1214 ⇒ If a short to voltage is found, repair the circuit fault. ⇓ If a short to voltage is not found 4.2. Replace the K5 Automatic Level Control Module. ⇓ If between 4.8–5.2 V
  9. Test for less than 1 V between the signal circuit terminal 3 and ground. ⇒ If 1 V or greater 5.1. Test the appropriate circuit for a short to voltage: DTC C103C = Circuit 1207 DTC C103D = Circuit 1210 DTC C103E = Circuit 1213 DTC C103F = Circuit 1216 ⇒ If a short to voltage is found, repair the circuit fault. ⇓ If a short to voltage is not found 5.2. Replace the K5 Automatic Level Control Module. ⇓ If less than 1 V
  10. Ignition OFF. Disconnect the connector at the K5 Automatic Level Control Module.
  11. Test for infinite resistance between signal circuit terminal 3 and ground. ⇒ If less than infinite resistance Repair the short to ground on the circuit. ⇓ If infinite resistance
  12. Test for less than 2 Ω between signal circuit terminal 3 and the other end of the circuit. ⇒ If greater than 2 Ω Repair the open/high resistance on the circuit. ⇓ If less than 2 Ω
  13. Test or replace the appropriate B11 Suspension 4 Corner Leveling System Position Sensor.
  14. Operate vehicle under the Coniditions for Running the DTC.
  15. Verify DTCs C103C, C103D, C103E, or C103F do not set. ⇒ If any of the DTCs set Replace the K5 Automatic Level Control Module. ⇓ If none of the DTCs set
  16. A fault is not currently present and may be an intermittent condition. Test B
  17. Verify that all B11 Suspension 4 Corner Leveling System Position Sensors are installed properly and are not damaged. ⇒ If all sensors are not installed properly or damage is found 1.1. Reinstall B11 Suspension 4 Corner Leveling System Position Sensors properly or replace as necessary. 1.2. Verify DTCs do not reset. ⇒ If DTCs reset, replace the K5 Automatic Level Control Module. ⇓ If DTCs do not reset 1.3. All OK. ⇓ If all sensors are installed properly and no damage is found
  18. Clear DTCs and operate the vehicle under Condition for Running the DTC.
  19. Verify DTCs do not reset. ⇒ If any DTCs reset Replace the appropriate B11 Suspension 4 Corner Leveling System Position Sensor ⇓ If DTCs do not reset
  20. A fault is not currently present and may be an intermittent condition. Test C
  21. Ignition ON.
  22. Adjust vehicle ride height to within specification using Inflate/Deflate functions in scan tool. Refer to: Trim Height Inspection and Trim Height Specifications
  23. Perform Automatic Level Control Trim Height Learn procedure. Refer to: Automatic Level Control Trim Height Learn
  24. Clear DTCs.
  25. Verify DTCs do not reset. ⇒ If DTCs reset Replace the K5 Automatic Level Control Module ⇓ If DTCs do not reset
  26. All OK. Repair Instructions Perform the Diagnostic Repair Verification after completing the repair. Front Suspension 4 Corner Leveling System Position Sensor Replacement Rear Suspension 2 or 4 Corner Air Leveling Position Sensor Replacement Control Module References for K5 Automatic Level Control Module replacement, programming and setup.