2005 Mercedes Benz CLK 320 Technical Service Bulletin # S-54_10-162 Date: 060412

Electrical - Voltage Drop Testing at The Fuses
Date: April 12, 2006
Order No.: S-B-54.10/162
Supersedes:
Group: 54
SUBJECT:
Model 164, 171, 199, 203, 208, 209, 210, 211, 215, 219, 220, 221, 230, 251 -
Quiescent Current Test Via Voltage Drop at the Fuses
This bulletin is for rapidly pinpointing closed-circuit systems responsible for voltage drop. It involves disconnecting fuses or CAN-distributors and
measuring the voltage drop directly at the fuse.
Measuring Voltage Drop:
1. Testing must be done on the installed fuse of the circuit 30 system (control module) using a suitable multimeter (e.g. Fluke 189) in the
microvolt range.
2000 Mercedes Benz CLK 320 (208.365) V6-3.2L (112.940) Page 308
2. For an accurate measurement, use appropriately sized pointed probes (Figure 1) to ensure sufficient contact with the opening in the fuse's
plastic housing.
NOTE:
Use probes from the electrical connection set (part no. W 220 589 00 99 00).
The quiescent current can be computed via Ohm's law from the measured voltage value and the internal resistance of the fuse measured.
Example calculation with a 30-A fuse
Fuse Internal resistance
2000 Mercedes Benz CLK 320 (208.365) V6-3.2L (112.940) Page 309
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