At the beginning of the week, the new truck broke down outside of town. After some fighting we got it back to the garage for diagnostics.

Once running again after purchasing a new battery charger and hours of fiddling, it was clear the battery was junk.

It looked like a cheapo battery, and it had no date indicators on it to clue me in to it’s age. Regardless…

Once a new battery was obtained, it was then possible to truly test the remainder of the charging system, namely the alternator.

Having started up the van easily with the new battery, checking voltage across the terminals showed that the rest of the charging system was in failure. This could have killed the battery during our repeated jump-starts to get it back home. Might have just been cheaper to tow it (note to self).

Lack of charging can be result of multiple issues other than a bad alternator in the Sprinters. The most common culprit are bad grounds. There are several on the driver (left in USA) side of the engine room that need to be checked.

• main chassis ground just above the battery negative terminal
• engine main ground on the left side engine mount, connected to the frame rail in the same area
• control system and accessory points below the battery near the headlamp

Having checked all those and cleaned them for good measure, the next easy win is checking the alternator fuse. On the sprinter there is a large plastic block bolted to the battery cable lead connector. From that block runs several high-amp wires (red) and one very large black wire, which heads to the alternator (this is the main charging feed). Inside this block there are plastic fuses of various amperage, high amperage, including a 200A fuse on the charging system side. This fuse is next checked for continuity to ensure that it is not open, and thus causing the charging system to fail.

Having inspected that, and seeing that it is in tact, the next avenue of investigation is the alternator itself.

Following the acquisition of some TORX Sockets (female, not male), sizes E12 and E6 where required, and about 1 hour of pulling parts to access top and bottom of the alternator, the item was removed.

Tomorrow I will be picking up a rebuilt alternator for around $210. Hopefully that brings the fun-van back to life!