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Checking Components And Wiring

Fig 1: Identifying Ignition OFF

GLL101045

Courtesy of VOLVO CARS CORPORATION

Ignition off
Check the throttle unit and engine control module (ECM) connectors. Check for contact resistance and oxidation.
Check the resistance value of the damper motor winding in the throttle unit. Take readings between throttle unit terminals #1 and #4 (component side). Check for an open-circuit. Check for a short-circuit.

NOTE:
The resistance of the motor winding in the damper motor is very low.

Check the damper motor (+) and (-) cable. Check for an open-circuit. Check for a short-circuit to ground. Check for a short-circuit to supply voltage.

Check between:
- Engine control module (ECM) terminal #A74 (#B14) and throttle unit terminal #4 (cable harness side)
- Engine control module (ECM) terminal #A75 (#B15) and throttle unit terminal #1 (cable harness side).
Also check the damper motor cables (+) and (-). Check for a short-circuit to each other.

Check that the shutter in the throttle unit is not blocked or sticking. Clean as necessary.

Remedy as necessary.

Other information:
- see CONNECTING THE BREAKOUT BOX
- see SIGNAL SPECIFICATION
- see COMPONENT SPECIFICATIONS
- see THROTTLE BODY, CLEANING
- see THROTTLE BODY
- see ENGINE CONTROL MODULE (ECM)
- see CONTENTS
Fig 2: Identifying Throttle Unit Connector Terminals
Courtesy of VOLVO CARS CORPORATION

Fig 3: Identifying Throttle Unit Connector Terminals
Courtesy of VOLVO CARS CORPORATION

Continue
Refer to ADAPTATION OF THE THROTTLE UNIT