What does Toyota fault code P1601 mean?

Q: What does Toyota fault code P1601 mean?

P1601 indicates: Check engine light; No driveability symptoms but code won't clear. Fix: Injector Correction Code (IMA) Discrepancy. LOGIC: The injector codes stored in the ECM do not match the physical injectors installed. ACTION: 1. Read the 30-character codes off the top of the injectors. 2. Compare to the data in the ECM using a scanner. FIX: Re-program the Injector Compensation Codes into the ECM using Techstream.

Toyota Fault Code

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P1601

Check engine light; No driveability symptoms but code won't clear.

System

Not specified

Symptom

Check engine light; No driveability symptoms but code won't clear.

Diagnosis & fix steps

Injector Correction Code (IMA) Discrepancy. LOGIC: The injector codes stored in the ECM do not match the physical injectors installed. ACTION: 1. Read the 30-character codes off the top of the injectors. 2. Compare to the data in the ECM using a scanner. FIX: Re-program the Injector Compensation Codes into the ECM using Techstream.

Red Seal field insights

If you swap injectors between cylinders or install a new one without "coding" it, the engine will run but it won't be optimized for emissions and noise.

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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