PeachParts Mercedes-Benz Forum - View Single Post

JamesDean · #24 05-02-2012, 01:24 PM

Testing the Cruise Control's Voltage Signals:

The 14-pin connector contains a few connections that can easily be tested with a cheap voltmeter/digital multimeter.

These connections are crucial to the operation of the cruise system. As they provide the unit with power, switch settings and brake signals.

If any of these numbers do not match, you most likely have a wiring issue or perhaps bad cruise control switch:

Step 1)
-Put your meter into the Volts DC range (20 VDC if you have manual range settings).
-Ground the black probe to a known ground or you can use pin 12 or 14. One of them might not have a pin in the harness that is OK.

Step 2)
During this step you will need to place your red/positive probe into the pin below and if necessary toggle the cruise stalk in the appropriate direction or apply the brake pedal.

-Test for voltages:

Pin 1 - Power - Should Read Battery Voltage (~12V)
Pin 2 - Decel/Set - 0 Volts initial, Battery Voltage when toggled.
Pin 3 - Off - Battery Voltage initially, 0 when toggled
Pin 4 - Accel/Set - 0 Volts initial, Battery Voltage when toggled.
Pin 6 - Resume - 0 Volts initial, Battery Voltage when toggled
Pin 8 - Brake Pedal - 0 Volts initial, Battery Voltage when toggled.

If you have any questions feel free to PM me or post up.

Hope this helps!

-Kris