Emergency Engine Start, Basic Function - GF54.10-P-9901A
Model all (CAR)
with code Z61 (Auxiliary battery for emergency start)
Overview
This document contains information on:
- General
- Function requirements
- Function
- Manual switch-in of special protection vehicle auxiliary battery
- Automatic switch-in of special protection vehicle auxiliary battery
General
If the state of charge is too low or the on-board electrical system battery is defective, the emergency engine start system allows the vehicle to be started by switching in an auxiliary battery.
Function requirements
- Sufficient state of charge of auxiliary battery
Function
Manual switch-in of special protection vehicle additional battery : By pressing the emergency engine start button in the glove compartment, the emergency start system relay (delay relay) is closed for approx. one minute. As a result, the special protection vehicle auxiliary battery is connected via the emergency start system relay (high current) parallel to the on-board electrical system battery and supports this battery. The start procedure can then be initiated using the start/stop button.
Automatic switch-in of special protection vehicle additional battery (comfort start):
With an on-board electrical system voltage of U < 12.2 V, the special protection vehicle auxiliary battery is connected parallel to the onboard electrical system battery for approx. three minutes when circuit 15 is switched on. For this purpose, the special vehicle multifunction control unit (SVMCU) actuates the emergency start system relay (high current) directly. The electronic ignition lock control unit sends the status of circuit 15 as well as the voltage of the on-board electrical system battery via the interior CAN to the special vehicle multifunction control unit (SVMCU).
With the engine running and a stable on-board electrical system voltage of U > 13 V, the emergency start system relay (high current) is actuated by the special vehicle multifunction control unit (SVMCU) after approx. one minute. As a result, the special protection vehicle additional battery is switched parallel to the on-board electrical system battery and is charged during vehicle operation.
The emergency engine start button and the emergency start system relay (delay relay) are supplied with power by the special protection vehicle auxiliary battery fuse block. The emergency start system relay (high current) is actuated via the special-purpose vehicle overvoltage protection.
| Function schematics | |||
| Function schematic for emergency engine start | Model 223 with code Z61 (Auxiliary battery for emergency start) | PE54.10-P-2518-97A | |
| Additional basic functions | |||
| Starting, basic function | GF07.10-P-1032A | ||
| Control units | |||
| Special vehicle multifunction control unit, basic function | Model all (CAR) with code Z61 (Auxiliary battery for emergency start) with code Z90 (Multifunctional control unit for special functions) except code 965 (Taxi/rental car - electrical pre-installation) | GF82.25-P-9892B | |
| Component descriptions | |||
| Emergency engine start button, component description | Model 223 with code Z61 (Auxiliary battery for emergency start) | GF54.10-P-0020A | |
| Overvoltage protection, component description | Model 223 with code Z61 (Auxiliary battery for emergency start) | GF54.10-P-0021A | |
| Battery, component description | Model 223 with code Z61 (Auxiliary battery for emergency start) | GF54.10-P-2003A | |
| Emergency engine start relay, component description | Model 223 with code Z61 (Auxiliary battery for emergency start) | GF54.15-P-0002A | |
| 12 V on-board electrical system fuse and relay module, component description | Model 223 with code Z61 (Auxiliary battery for emergency start) | GF54.15-P-0006A |