|
Q: How will the oscilloscopes be used to diagnose a stalling vehicle?
-Customer Inverview
A: From the outset, engine stalling (like all diagnostic procedures) needs to be evaluated by an interview with your customer as they have all the answers and more importantly the history/sequence of events
A basic inspection must never be overlooked before any diagnosis as it is all too easy to attack vehicles with an array of test equipment when in fact our concern could be contaminated fuel!
Confirmation of the customers concern is paramount and ideally with a scan tool attached to gather valuable data during the fault condition. This is not always possible as faults are often intermittent and dependent on driving conditions and so again, the customer interview will assist
-Road Testing
Diagnostic trouble codes are always the first port of call along with any serial data from your chosen Scan tool. Road testing the vehicle with your scan tool connected whilst trying to simulate the condition will also assist to provide target areas for further diagnosis and testing and this is where oscilloscope becomes invaluable.
-Measure Components with an Oscilloscope
Armed with all the information above the technician will be required to follow a fault code flowchart if a relevant fault code is present, or, armed with his knowledge of the system will begin to test and measure components of the engine management with an oscilloscope that could be responsible for the customers symptom.
To give a typical example, let’s take a gas engine stalling when stopping at junctions but no fault codes evident. A description of the engine idle control system is required and a list complied of possible components that could produce the staling. From this list the technician may decide to test the, oxygen sensor, airflow meter, and throttle position sensor. The order of tests depends on the ease of access to these components but with a 4 channel scope all these inputs can be measured and monitored in real time on one screen.
Using the oscilloscope gives the technician the advantage to monitor (in real time) the actual live signals and compare them to the processed data from the scan tool.
|
Related collections:
- · Auto|Threads: 1, Subscribe: 0
- · Auto SCOP|Threads: 1, Subscribe: 0
|