Is there a way to read DTCs on a LS1B bench setup? I can trigger and clear(V7.5 only) unknown DTCs, but get no DTCs stored if I try to read them. Should be plenty of them on a bench setup.
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Is there a way to read DTCs on a LS1B bench setup? I can trigger and clear(V7.5 only) unknown DTCs, but get no DTCs stored if I try to read them. Should be plenty of them on a bench setup.
You'd think so but I've noticed on the older PCM's they sometimes don't set any DTC's on the bench, late model stuff on the other hand you get pages!
Yes. Same result with HPT and with multiple LS1B PCMs. I can wire up a throttle/pedal/TAC and cause the throttle to disable by doing something that would set a DTC. It will re-enable if I clear DTCs. So the fault is definitely stored somewhere.
The LS1B has conditions that have to be met before some of the DTC tests are run... those conditions never happen on the bench.
Looks like the PCM needs to see a crank sensor signal after a battery dis-connect/re-connect before it will report any DTCs. Even DTCs whose tests run without the engine running. I simulated a 600 RPM signal on the CKP input, then I could read the stored DTCs. As long as I don't disconnect the battery for some period of time, I don't need to apply a CKP signal again...I can still read DTCs on subsequent Key cycles. I tried a 5 minute disconnect and could still read DTCs without applying a CKP signal.