V49 Xiii

Plug Designations in CEB Wiring Diagram

Example: Designation B22 in CEB wiring diagram means:

single contact is located in "plug B", in the first module element (2) and on plug terminal 2.

All sleeve-type terminals of wire harness plugs consist of spring contacts, with which safe and almost constant contact force is guaranteed.

To remove a sleeve-type terminal from a plug receptacle the pertinent element must first be removed from the total plug, since sleeve-type terminals are also held in place by plug modules. Only then can the plug locking tabs be unlocked with a special pressing-out tool.

The alternator was completely revised for Mod. 82. It was equipped with uprated diodes (wired in parallel), better cooling and a new regulator.

The regulator improved again from Mod. 84. It can be identified by the aluminium housing and can be installed in alternator from Mod. 82 onwards.

The field circuit

A field current must flow through the rotor winding in order to excite the alternator, i. e. built up a magnetic field in the rotor.

However, this field current flows only if a load is switched on in the field circuit (between ignition switch and alternator). This load takes the form of the charge indicator lamp.


Mod. 83


Mod. 83

Mod. 84

When the ignition (terminal 15) is switched on, "positive" is applied to the charge indicator lamp. Ground (earth) must be applied to the lamp via the alternator and regulator to make it light up. When the engine is running and if the alternator and regulator are in order, a voltage is supplied via D+/61 (regulating voltage) by the alternator as a result of the magnetic field in the rotor. This means that the charge indicator lamp receives "positive" at both sides and thus goes off. The alternator charges and the regulator is in order. If the regulating voltage were too high or too low in comparison with the voltage at terminal 15, the charge indicator lamp would glow because of the different potentials at the lamp.

A shunt resistor is installed from Mod 79 because the charge indicator lamp was reduced in si^e to 1.2 W (formerly 3 W). The internal resistance of the lamp must be reduced in order to allow a sufficiently large field current to flow. A 3-Watt lamp has an internal resistance of approx 60 £2 and a 1,2-Watt lamp one of approx. 170 £2.


Current I at 3 W

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