APRILIA SHIVER 900, Service Station Manual

Page: 156 / 444

Troubleshooting
•
Check the continuity of the circuit from the probe connector (PIN 1 and PIN 2) towards the
probe: replace the lambda probe if there is no continuity; if there is continuity, check the
sensor connector and the Marelli control unit connector: if NOT OK, restore; if OK, check
the continuity between the ENGINE connector PIN 9 and PIN 38 and restore the wiring
harness.
DIAGNOSTIC TOOL: LOGIC ERRORS
P0154 Rear lambda probe
Functional diagnosis:
•
no switching from high / no switching from low
Error cause:
•
If no switching from high: is shown when the ratio control is in closed loop and when the
secondary air valve is not operating. The error is validated if the engine is in CUTOFF status
and the probe signal is close to 1V, or if the engine is in another operating condition that
requires the injection but the switching from the"HIGH RATIO" to "LOW RATIO" is missing
for a certain"adjusted" number of dead points (PMS or TDC).
•
If no switching from low: is shown when the ratio control is in closed loop and when the
secondary air valve is not operating. The error is validated if during the ratio control stage,
the switching from "HIGH RATIO" to "LOW RATIO" is missing for a certain"adjusted" number
of upper dead points (PMS or TDC).
The instrument panel indicates this error by lighting up in a fixed manner the MI warning light.
Troubleshooting:
•
If no switching from high: the fault may be generated in the supply system (poor pin sealing)
or in the probe. Check the wiring harness. if NOT OK restore; if OK, replace the lambda
probe.
•
If no switching from low: the fault may be generated in the supply system (dirty injector, low
fuel supply system pressure) or in the probe. Check the wiring harness. if NOT OK restore;
if OK, replace the lambda probe.
•
For the (non polarised) type of probes, this error may be caused also by a short circuit to
the wiring harness ground.
NOTE
THIS ERROR DISABLES THE RATIO CONTROL IN CLOSED LOOP.
Electrical system
SHIVER 900
ELE SYS - 156