2001 Volvo V70 XCFACTORY OEM SERVICE PROCEDURE

Starter motor

Fig 1: Starter Motor Communication Diagram
GLL146445Courtesy of VOLVO CARS OF NORTH AMERICA.

Manual transmissions 

The starter motor (6/25) is operated by turning the key in the ignition switch (3/1) to position III.

  • For transmissions with  a clutch interlock (certain markets), a signal is transmitted from the ignition switch to the engine control module (ECM) (4/46). The engine control module (ECM) detects the position of the clutch pedal sensor (7/123). The engine control module (ECM) transmits data to the central electronic module (CEM) (4/56) via the control area network (CAN) about the position of the pedal. The central electronic module (CEM) requires a signal that the clutch is pressed down and that the key is in position III before it will send a signal to the relay (2/35). When the relay is activated, the solenoid in the starter motor is powered
  • For transmissions without  clutch interlock, the central electronic module (CEM) (4/56) activates relay 2/35 and powers the solenoid in the starter motor (6/25).

The starter motor turns for as long as the key is in position III. If the engine has been started once, there is a Limp Home function so that the engine can be started again even if there is a fault in the control area network (CAN). This function is active for a brief period after the key is removed from the ignition switch. After this time the car will not start because there is no communication for the immobilizer between the central electronic module (CEM) and the engine control module (ECM).

Automatic transmission 

The starter motor (6/25) is operated by turning the key in the ignition switch (3/1) to position III.

  • For transmission 4T65EV, a signal is transmitted from the gear-shift position sensor (3/71) via the transmission control module (TCM) (4/28) to the central electronic module (CEM) (4/56) indicating that the gear selector is in position P/N
  • For AW transmissions the signal is transmitted directly from the gear-shift position sensor to the central electronic module (CEM). The central electronic module (CEM) requires this signal and a signal indicating that the key is in position III before it will send a signal to the relay (2/35). When the relay is activated, the solenoid in the starter motor is powered.

The starter motor turns for as long as the key is in position III. If the engine has been started once, there is a Limp Home function so that the engine can be started again even if there is a fault in the control area network (CAN). This function is active for a brief period after the key is removed from the ignition switch. After this time the car will not start because there is no communication for the immobilizer between the central electronic module (CEM) and the engine control module (ECM).

Factory Service Tools

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

Rather have a pro handle this?

A certified mobile mechanic comes to your home or office. They bring the tools, you stay comfortable. No tow truck, no waiting room, no surprises.

Comes to youSame-day available12-month warranty
Get a Free Quote

No obligation. See pricing before you book.