CM850 Electronic Control System – FAULT CODE 2216 (ISB/QSB Automotive or Industrial Application)

Fuel Pump Delivery Pressure – Data Valid but Above Normal Operational Range – Moderately Severe Level


Overview

CODE REASON EFFECT
Fault Code: 2216
PID: P94
SPN: 94
FMI: 0
LAMP: Amber
SRT: 

Fuel pump delivery pressure – data valid but above normal operational range – moderately severe level. The ECM has detected fuel pressure in the fuel rail that is higher than the commanded pressure.

None or possible engine noise associated with higher injection pressures (especially at idle or light load). Engine power is reduced.

Fuel System
SMALL | MEDIUM | LARGE

Circuit Description

The electronic control module (ECM) monitors engine operating conditions, including the reading of rail fuel pressure, and changes the flow command either to increase (OPEN the electronic fuel control actuator) or to decrease (CLOSE the electronic fuel control actuator) the fuel supply to the high-pressure pump.

Component Location

The electronic fuel control actuator is installed on the high-pressure fuel pump. Refer to Procedure 100-002 for a detailed component location view.

Shop Talk

An electronic fuel control actuator with excessive leakage will result in high rail fuel pressures at idle or light load, and Fault Code 2216 will be logged. A restriction in the fuel-drain-to-tank return line can prevent excess fuel from exiting the high-pressure fuel pump. This excess drain fuel can enter the pumping chamber and pressurize the rail. Check the fuel drain line restriction. High resistance or an open circuit in the electronic fuel control actuator can cause this fault to log. Air in the fuel can result in pressure changes that would cause this fault to log. High low-pressure pump output pressure could cause this fault to log, as could tampering with the rail fuel pressure sensor.

Fault Code 2216 is activated whenever the engine is loaded (nonzero fueling) and measured fuel pressure is higher than the commanded fuel pressure.

If the drain line is restricted completely, the high-pressure fuel pump will fail, causing internal leakage. Prior to pump failure, fault codes indicative of a drain line restriction will occur. The Fault Codes are 449, 2216, or 2293. Following the failure, these fault codes will go inactive and Fault Code 2215, which is indicative of leakage, will be active. If troubleshooting Fault Code 2215 results in replacement of the pump and there are inactive counts of Fault Codes 449, 2216, or 2293, the drain line must be inspected and measured for restriction. This is to prevent repeat high-pressure pump failures.

Refer to Troubleshooting Fault Code t05-2216

Last Modified:  08-Jul-2010