I am new to this forum and I just purchased a '03 Anniversary vert and I checked for codes today. It had several from the LDM and RDM but I think they were minor. The one that worries me is C0620H which is in the RTD unit. I did a search and cannot find this code listed except on 07 models at digital corvette. Can someone please tell me what the code means and what causes it. I am getting ready to order the service manual, but I would like to know what it is. Thanks in advance.

 

Hope this helps. Kinda long. I droped the H off the end and found this.


Document ID# 850725
2003 Chevrolet Corvette


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DTC C0615, C0620, C0625 or C0630
Circuit Description
The ESC module supplies 8 volts to the position sensors. The position sensors use the supplied 8 volts to produce an analog output range of 0-5 volts. The ESC module calculates vehicle suspension settings based upon the voltage levels received back from the position sensors. The ESC model monitors for an out of range condition.

Conditions for Running the DTC
• The ignition ON.

• The ESC function enabled.

Conditions for Setting the DTC
• The ESC module senses position sensor output voltage under 0.35 or over 4.75 volts.

• The condition must be detected for 1 second in 4 consecutive ignition cycles.

Action Taken When the DTC Sets
• Stores a DTC C0615, C0620, C0625 or C0630 in the ESC memory.

• Provides shock absorber solenoid control based on the vehicle speed only.

• Sends a message to the IPC to display the SERVICE RIDE CONTROL message.

Conditions for Clearing the DTC
• The ESC module senses the correct position sensor output voltage between 0.35-4.75 volts.

• A history DTC will clear after 100 consecutive ignition cycles if the condition for the malfunction is no longer present.

• Use the IPC clearing DTC feature.

• Using a scan tool.

Diagnostic Aids
• The following conditions may cause an intermittent malfunction to occur:

- There is an intermittent open or short in the position sensor circuit.

- Bent, disconnected, or damaged position sensor linkage.

• When using a scan tool in order to read position sensor voltage, always make sure the vehicle is sitting with the full vehicle weight on its wheels. Measuring position sensor voltage with the vehicle raised and the wheels hanging may lead to incorrect diagnosis.

• An intermittent DTC C0615, C0620, C0625 or C0630 may produce a random firm/soft ride condition.

• The ESC module uses an ignition cycle counter diagnosis approach to set this DTC. This requires the ESC module to detect a malfunction 4 times before setting the DTC. To disable this feature, use a scan tool to clear all DTCs before performing diagnosis procedures.

• If the DTC is a history DTC, the problem may be intermittent. Using a scan tool, monitor the position sensor voltage while test driving the vehicle or moving the wiring and connectors. This can often cause the malfunction to occur.

Test Description
The numbers below refer to the step numbers on the diagnostic table.

This step tests the position sensor signal voltage range using a scan tool. Normal signal voltage is between 0.35-4.75 volts.

This step tests the position sensor signal voltage range using a scan tool with the sensor disconnected. Normal signal voltage range with the sensor disconnected is approximately 0 volts.

This step tests for the proper operation of the circuit in the high voltage range. If the fuse in the jumper opens when you perform this test, the signal circuit is shorted to ground.

This step tests for a short to voltage in the 8-volt reference circuit.

This step tests for high resistance or an open in the ground circuit.

This step tests for an open or high resistance in the position sensor ground circuit.

Step
Action
Value(s)
Yes
No

Schematic Reference: Suspension Controls Schematics

Connector End View Reference: Suspension Controls Connector End Views

1
Did you perform the Electronic Suspension Control Diagnostic System Check?
--
Go to Step 2
Go to Diagnostic System Check - Electronic Suspension Control

2
Install a scan tool.
Turn ON the ignition, with the engine OFF.
With the scan tool, observe the Position Sensor data parameter in the ESC data list.
Does the scan tool indicate that the Position Sensor data parameter is within the specified range?
0.35 - 4.75 V
Go to Diagnostic Aids
Go to Step 3

3
Turn OFF the ignition.
Disconnect the position sensor.
Turn ON the ignition, with the engine OFF.
With a scan tool, observe the Position Sensor data parameter.
Does the scan tool indicate that the Position Sensor data parameter is less than the specified value?
0.35 V
Go to Step 4
Go to Step 10

4
Turn OFF the ignition.
Connect a 3-amp fused jumper wire between the 8-volt reference circuit of the position sensor and the signal circuit of the position sensor.
Turn ON the ignition, with the engine OFF.
With a scan tool, observe the Position Sensor data parameter.
Does the scan tool indicate the Position Sensor data parameter is greater than the specified value?
4.75 V
Go to Step 5
Go to Step 8

5
Disconnect the fused jumper wire.
Measure the voltage between the 8-volt reference circuit of the position sensor and the ground circuit of the position sensor.
Does the voltage measure less than the specified value?
8 V
Go to Step 6
Go to Step 7

6
Turn OFF the ignition.
Measure the resistance from the ground circuit of the position sensor to a good ground.
Does the resistance measure less than the specified value?
5 ohms
Go to Step 12
Go to Step 11

7
Test the 8-volt reference circuit of the position sensor for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?
--
Go to Step 16
Go to Step 13

8
Test the 8-volt reference circuit of the position sensor for a short to ground, a high resistance, or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?
--
Go to Step 16
Go to Step 9

9
Test the signal circuit of the position sensor for a short to ground, a high resistance, or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?
--
Go to Step 16
Go to Step 13

10
Test the signal circuit of the position sensor for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?
--
Go to Step 16
Go to Step 13

11
Disconnect the ESC module.
Test the ground circuit of the position sensor for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
--
Go to Step 16
Go to Step 13

12
Inspect for poor connections at the harness connector of the position sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?
--
Go to Step 16
Go to Step 14

13
Inspect for poor connections at the harness connector of the ESC module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?
--
Go to Step 16
Go to Step 15

14
Replace the applicable position sensor. Refer to Front Position Sensor Replacement - Electronic Suspension or Rear Position Sensor Replacement - Electronic Suspension .

Did you complete the replacement?
--
Go to Step 16
--

15
Replace the ESC module. Refer to Electronic Suspension Control Module Replacement .

Did you complete the replacement?
--
Go to Step 16
--

16
Use the scan tool in order to clear the DTCs.
Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.
Does the DTC reset?
--
Go to Step 2
System OK



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Document ID# 850725
2003 Chevrolet Corvette

 

Thank you so much for your prompt and thorough response. I have reset the code and will check it again tomorrow. If I can't figure it ot, I'll take it to the dealer for repair. Where do you get a scan tester to check the sensors. I have an Actron CP9145. Will this allow me to check the sensor voltages. By the way this may be a stupid question, but where is the OBD II port on the C5 Convertible? Thanks in advance.