What it means
Voltage on the ICP regulator control line is below the expected window. Usually a short to ground or a shorted regulator coil.
At a glance
- Usually lights the check-engine light
How it works
The injector control pressure regulator circuit controls an electrically actuated regulator on vehicles equipped with an injector-control-pressure system. The module detects that the control line is below its expected electrical range and sets P2624; a short to ground, a shorted regulator coil, or poor connector contact can pull it low. The code alone does not identify a particular fuel or injector design.
Common causes
Most likely first.
- Control wire shorted to ground
- Internal short in regulator coil
- Connector pins corroded - high contact resistance
Symptoms
- Check-engine light
- Hard starting, rough running, or reduced engine power
How to diagnose it
- Check freeze-frame data and related codes to establish when the low-circuit fault occurs and whether engine symptoms coincide.
- Inspect the regulator connector and harness for moisture, corrosion, crushed insulation, or a wire rubbed through to ground.
- Check connector terminal fit and condition; corrosion or loose pins can create abnormal readings under load.
- Using the vehicle wiring diagram, test the control wire for an unintended connection to ground and isolate sections as needed.
- Measure the regulator coil against the manufacturer's specification to identify an internal short.
- If the harness and coil check out, verify the module's control output and grounds using the manufacturer's diagnostic procedure.
Common fixes
- Dry and clean the regulator connector and restore tight terminal contact.
- Repair a control wire shorted to ground or replace damaged harness sections.
- Replace the regulator if its coil is shorted.
- Repair corroded or loose connector terminals.
- Address a module output fault only after confirming the regulator and wiring are sound.
Can I keep driving?
If the engine starts and runs normally, limit driving to a short trip for diagnosis; hard starting, rough running, or reduced power can worsen unexpectedly. Avoid demanding loads and stop if the engine stalls.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.