How to Troubleshoot DTCs
How to Troubleshoot DTCsThe troubleshooting procedures assume that the cause of the problem is still present and the ABS, VSA indicators, and/or trailer stability assist warning are still on. Following a troubleshooting procedure for a code that has been cleared but does not reset can result in incorrect diagnosis.
1. Question the client about the conditions when the problem occurred, and try to reproduce the same conditions for troubleshooting. Find out when the ABS, VSA indicators, and/or trailer stability assist warning came on, such as during activation, after activation, when the vehicle was traveling at a certain speed, etc. If necessary, have the client demonstrate the concern.
2. When the ABS, VSA indicators, or trailer stability assist warning does not come on during the test-drive, but troubleshooting is done based on the DTC, check for loose connectors, poor contact of the terminals, etc. before you start troubleshooting.
3. After troubleshooting, or the repairs are done, clear the DTCs, and test-drive the vehicle under the same conditions that originally set the DTCs. Make sure the ABS, VSA indicators, and trailer stability assist warning do not come on.
4. Check for DTCs from other systems which connected via F-CAN. If there are DTCs that are related to F-CAN, the most likely cause was that the ignition switch was turned to ON (II) with the VSA modulator-control unit connector disconnected. Clear the DTCs. Check for fuel and emissions codes, first. Be sure to troubleshoot those first.
Intermittent Failures
The term "intermittent failure" means a system may have had a failure, but it checks OK now. If the indicator(s) of the system does not come on, check for loose connectors or poor contacts in the terminals related to the circuit that you are troubleshooting.