Så här säger servicemanualen...
"Detonation Protection (DET)/RPM Limit
When DET is sensing and taking action to reduce
detonation, the driver may notice a drop in engine RPM
and/or reduced performance.
The ECU will illuminate the instrument cluster check
engine LED and display “dET” on the LCD screen
whenever the DET system is active.
If the ECU determines the detonation cannot be controlled
by normal means and further operation may cause engine
damage, the check engine LED will flash, the instrument
cluster will display “dET”, and the ECU will limit the
maximum engine speed to 6,500 RPM. The RPM limit will
remain active until the driver turns off and restarts the
engine.
If the detonation RPM limit occurs, a diagnostic trouble
code (DTC) will be registered. Digital Wrench will display
one of the following codes: 1352/0 (P1336), 1352/16
(P2336), 1353/0 (P1337), or 1353/16 (P2337)."
Hur mycket varvar den om du håller stumt?
Jag lade upp en servicemanual förut för PRO-ride här;
http://forum.snowmobile.se/showthread.php?t=53304
Manualen heter 2010-2012 PRO-RIDE RUSHSwitchbackRMK Service Manual.pdf
I den står lite tips för felsökning - om än något knapphändiga instruktioner.