Liebherr Fault Code
Free · no signupP1192
DEF Light Flashing / Power Derate
System
Emissions / DEF
Symptom
DEF Light Flashing / Power Derate
Diagnosis & fix steps
LOGIC: DEF Tank Heating Valve Circuit Short to Ground.
ACTION: Measure internal coil resistance of the coolant-driven DEF tank heating valve. Check harness leads running to the DEF tank module for insulation damage.
Red Seal field insights
Cold Weather Safeguard: Prevents DEF freezing in sub-zero climates; a shorted valve forces the ECU to flag a cold-start emissions fault.
Same code keeps coming back?
That's a program problem, not a part problem. Book a 30-minute uptime review with Grant, a Red Seal Heavy Duty Technician.
Read before you touch anything
- This is general reference information, not a repair manual. It is for trained, qualified technicians.
- Fault codes, meanings and procedures vary by model, serial number and software version. Confirm the code and the procedure against the manufacturer's service manual before acting.
- Follow the OEM service manual, torque specs and your site's safety procedures: lockout/tagout, block raised equipment, relieve hydraulic, fuel and air pressure, and let hot systems cool.
- You use this information at your own risk. Adventure Mechanical and AM Fleet Integrity accept no liability for damage, injury, downtime or loss arising from its use.
- Not affiliated with or endorsed by any manufacturer. Brand names are used only to identify the equipment a code applies to.
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Start your free trialRelated Liebherr fault codes
- P1198AdBlue Warning Light / Derate Active
- P1195DPF Warning Light / High Idle
- P1189Active Torque Derate / AdBlue Lamp
- P1188Active Torque Derate (Max 75% Torque Cap)
- P1223PDE Data Not Recording.
- P1187-00Warning Level 1. Yellow alert on dash; no power loss yet, but a timer has started.
- P2047-00Limp Mode. DEF dosing stops immediately.
- P1187DeNOx Warning / Slight Power Reduction
- P1122-00Dosing Failure. AdBlue/DEF is not being sprayed into the exhaust.
- P204C-00DEF Derate. Check Engine light on; AdBlue/DEF pressure fails to build; machine may limit RPM/torque.