Engine Coolant Temperature High
The DD-110-0 (Detroit Diesel DD Series) diesel fault code means: Engine Coolant Temperature High. This is a serious severity code.
This is a standard J1939 fault, not a proprietary code. DD-110-0 is how this equipment displays SPN 110 with FMI 0 (data valid but above normal — most severe) under the SAE J1939 standard used across heavy equipment. The same SPN can appear on any J1939-compliant machine regardless of brand — so cross-referencing it against your engine maker's documentation is valid even when the equipment brand differs.
- Keep driving?
- No — stop driving
- DIY difficulty
- intermediate
- Estimated cost
- $1,200-$3,800
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Common Symptoms
- Check Engine Light / Amber Warning Lamp illuminated
- Red Stop Lamp on, engine derate or forced shutdown
- Engine derate (reduced torque / 5 mph limp)
- Overheat warning
Probable Causes (Ranked by Likelihood)
- Low coolant level Very Likely
- Failed thermostat Likely
- Plugged radiator core Likely
- Failed water pump Possible
- Fan clutch not engaging Possible
- Head gasket failure (DD15 known issue at high miles) Possible
Frequently Asked Questions
What is Detroit Diesel fault code DD-110-0?
Detroit Diesel fault DD-110-0 (SPN 110 FMI 0) indicates: Engine Coolant Temperature High. It is a serious-severity fault and is commonly seen on DD13/DD15/DD16 engines in Freightliner and Western Star chassis.
Can I drive my Freightliner or Western Star with fault DD-110-0?
It depends on severity. Critical and serious faults trigger derate or engine shutdown — do not continue driving. Moderate faults usually allow continued operation short-term but schedule repair to prevent cascading aftertreatment damage.
How much does it cost to fix Detroit Diesel fault DD-110-0?
Estimated repair cost is $1,200-$3,800. Sensor/harness fixes fall at the low end; turbo actuator, injector, aftertreatment component, or head gasket repairs fall at the high end. Detroit DDDL software and sometimes factory parameter reset are required for proper reset.
Mechanics Guide Step-by-step diagnosis
Step-by-Step Diagnostic Procedure
Verify coolant level cold; top off if low.
Test thermostat by watching temp rise and opening point via DDDL.
Inspect radiator core for fin plugging or debris.
Check fan engagement via DDDL output test.
If coolant loss with no external leak, pressure-test for head gasket failure.
Sources 1
This page is built from documented references. Verify against your own service info before repair work.
- SAE J1939-73Application Layer: Diagnostics (defines the SPN/FMI fault-identifier framework)
Commonly Affected Vehicles
- Freightliner Cascadia with DD15
- Freightliner Cascadia with DD13
- Freightliner Cascadia with DD16
- Western Star 4700 with DD13/DD15
- Western Star 4900 with DD15/DD16
- Western Star 5700 XE with DD15
- Freightliner M2 106 with DD13
- Freightliner M2 112 with DD13
Related Codes
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