GF07.61-P-3007CY ME-SFI Maximum Engine Speed Limitation, Function

GF07.61-P-3007CY ME-SFI Maximum Engine Speed Limitation, Function
- up to model year 08


The ME-SFI [ME] control unit (B70) detects the engine speed via the crankshaft Hall sensor signal (N3/10). To protect the engine and the drive train, the maximum engine speed is limited, by:
^ Reducing the opening angle of the throttle valve
^ Taking back the ignition angle
^ Shutoff of fuel injection valves (Y62)

1. Transmission overload protection
1.1 Torque converter protection (with automatic transmission 722.9)
In order to protect the torque converter in selector lever positions P or N (no power flow) from excessive static internal pressure, the maximum engine speed is limited to approx. 4200 rpm.

1.2 Manual transmission protection (with manual transmission 716.6)
The maximum engine speed for a stationary vehicle is limited to about 4000 rpm to protect against damaging the manual transmission.

2. Limiting maximum engine speed when driving
In order to protect the engine from the consequences of impermissibly high engine revs, engine speed is limited to approx. 6000 rpm.
The driving mode is detected from the vehicle speed signal.

3. Throttle valve actuator (M16/6) defective
In the event of a defective throttle valve actuator, the maximum engine speed is limited in idle to approx. 1400 rpm and in driving mode to approx. 1800 rpm.

4. Missing variant coding
If no variant coding exists, the maximum engine speed is limited to about 2400 rpm.