Volvo Service Bulletin 3-30-04

Product Section Group No. Date Title
B 3 30 04 11.90 Action in the event of falls in voltage in the starter motor and charging circuits

Description: Action in the event of falls in voltage in the starter motor and charging circuits

Falls in voltage between batteries and the alternator are frequently the reason for poor battery charging. Corroded or paint-covered contact surfaces in the starter motor and charging circuits usually cause such a fall in voltage. The following action should be taken to solve these problems.

Tools:

Materials

  1. Turn off the voltage by switching off the battery main switch.
  2. Remove all the battery cable shoes from the batteries and the battery minus connection in the chassis.
  3. Use tools 1158940 and 1158941 and clean the battery terminals and the battery cable shoes. Remove any oxide or other deposits from the minus connection in the frame.

Remarks. If the battery cable shoe was incorrectly fitted (see Figure 1), the battery terminal must be carefully reamed using tool 1158941. If this is not done, the contact surface between the battery terminal and the battery cable shoe will be insufficient when the battery cable shoe is fitted correctly. This also means that there will be a high risk of oxidation in the space between the upper part of the battery terminal and the battery cable shoe. Protect the battery terminals, battery cable shoes and the minus connection in the frame with Dinitrol after they have been fitted.

N.B. If the battery is changed, the battery cable shoes must always be cleaned carefully.

Battery cable shoe incorrectly fitted, not fully tightened
Figure 1. Battery cable shoe incorrectly fitted, not fully tightened.
 
Battery terminal must be reamed!
Figure 2. Risk of oxidation, the battery terminal must be reamed!

Alternator and starter circuits
Figure 3. Alternator and starter circuits

  1. Remove and clean the positive cable connections in the alternator and starter circuits, at the battery isolator switch (1), the circuit breaker for the starter (2), the starter (3), the rear fuse box (4) and the alternator or alternators (5).
  2. Remove and clean the earth cable connections between the starter (2) and the frame, and between the alternator (5) and the frame.

Note: If more than one cable is to be connected to one of the connections mentioned above, always fit the thickest cable closest to the inside. Then fit the other cables in order of thickness.