Engine Block Heater - Timer Circuits: Diagnosis Volvo C70 I

Reading Off And Erasing Diagnostic Trouble Codes (DTCs)

This function allows stored diagnostic trouble codes (DTCs), counters and frozen values to be read and erased.

A diagnostic trouble codes (DTCs) can only be erased when all diagnostic trouble codes (DTCs) have been read off at least once and the reason for the fault has been corrected.

When the control module detects a fault the values of certain parameters are frozen and can be read off with the diagnostic trouble code (DTC).

Frozen values for the following parameters can be read off

1. The position of the motors and their speed (via potentiometers)
2. The status of the buttons on the control panel.
3. Motors activated (front/rear) or not
4. Supply voltage to control module

For more information Refer to: Frozen values .

Connecting the Volvo Scan Tool (ST)

1. Ignition OFF.
2. Install memory cassette.
3. Connect Volvo Scan Tool (ST) to data link connector (DLC) using adapter.
4. Ignition ON.
5. Turn on power to the Volvo Scan Tool (ST).
6. Select language, car and function group.
7. Select required system.
8. Select LEFT or RIGHT SEAT.
9. Select DIAGNOS TEST to read out and erase diagnostic trouble codes (DTCs), counters and frozen values and for activating components/functions.
10. Select MONITOR TEST and SCROLLING LIST to read off the control module input and output signals.
11. Select CM ID to read off the part number of the control module.

Scheme 4

1. Take 2 connectors Part No. 968515 -7 and 968516-5 .
2. Clamp to 4 lengths of cable, at least 1.5 mm2(in2). Length must not exceed 3 meters, since voltage drop in cable increases with length which could supply too low a voltage to seat.
3. Attach terminal pins, Part No. 979002-3 and 973117-5 , to cables and press into connectors as per figure.