What does RAM fault code P208D mean?

Q: What does RAM fault code P208D mean?

P208D indicates: DEF gauge reads empty when full; Service DEF system message; 5 MPH derate. Fix: DEF Reductant Pump Control Circuit High. LOGIC: The ECM detects an electrical failure or a mechanical blockage in the DEF pump motor. ACTION: 1. Check the wiring harness at the DEF tank (near the spare tire). 2. Check DEF pump fuse. FIX: Replace the DEF Pump/Reservoir assembly (Unit is inside the tank).

RAM Fault Code

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P208D

DEF gauge reads empty when full; Service DEF system message; 5 MPH derate.

System

Not specified

Symptom

DEF gauge reads empty when full; Service DEF system message; 5 MPH derate.

Diagnosis & fix steps

DEF Reductant Pump Control Circuit High. LOGIC: The ECM detects an electrical failure or a mechanical blockage in the DEF pump motor. ACTION: 1. Check the wiring harness at the DEF tank (near the spare tire). 2. Check DEF pump fuse. FIX: Replace the DEF Pump/Reservoir assembly (Unit is inside the tank).

Red Seal field insights

In winter, DEF can freeze and crack the internal pump housing. Ensure your DEF tank heater is working; if it's not, the pump will fail every time it hits -11°C (12°F).

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.

Book an uptime review

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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