DIY: Build your own positive battery cable 9456836 for the 850

[erikv11]

If you remove the cover to the fuse box, you will see where the B+ wires enter the box, but then they disappear under the plastic fuse holders, as part of a large bundle. I don't know if you can get at the connection point down there. Perhaps you can just go to a terminal in the fuse box, to measure voltage?

So I went ahead and tried out the amazing and mysterious search button . It revealed that while B+ cable failures are very common on 98-00 cars, they are rare on 850s. So rare that I didn't find any examples at all; granted, I didn't look that hard. If the battery end of the B+ in your 850 is corroded then replace the connector there, e.g. https://www.matthewsvolvosite.com/forums/vie ... hp?t=60592. If the end at the battery looks fine, the cable is probably fine. I'd at least test it at the fuse box.

[Redneck]

I keep all my electrical connections in top shape. I have seen these pictures earlier and I searched this and other sites on this subject. This is what motivated me to check my own B+ cable and connectors. Lack of discussion about B+ connector problems on 850 is good news. Thank you for pointing that out.

This is a very important connection as it delivers power to all car's electronics. It would be worth to check it and clean it up preemptively to improve contact and prevent any intermittent unexplained malfunctions. Loose connections, failing crimps, minor surface oxidation due to age of the copper are my primary concern. I always cleaned every accessible electrical connector during any repair including inside of every relay.

It is off-topic in this thread, but I see my transmission splatters fluid around the wiring harness. That may lead to insulation failure. I need to examine that. That is my biggest problem that I will probably never fix. I think the transmission enclosure seal is failing somewhere. I know for sure it is transmission fluid. I've had that problem for many years, but now there is more leakage than before. I need to keep a board under the car to prevent drips on concrete.

[abscate]

ATF is not going to hurt wire insulation. There are actually wires bathed in ATF in my VW transmission.
Get a shoe tray or water heater pan under the car so you don't have a big piece if ATF soaked wood to deal with.

Neil would just drain the leaked ATF through discarded panty hose and rebottle it for sale. Waste not, want not.

[bugs11]

For anyone that's interested, I just ordered all the parts as in the OP and price was $28.63.

[mrbrian200]

Put a bead of silicone/rtv sealant under the shrink tubing before you heat it. Same as black tape, shrink tubing often does not fully seal moisture out, and moisture that does work its way in gets trapped and eventually rots the copper.
Exterior circuits I generally seal up similar to NEC codes for submerged AC/high voltage wiring. On vehicles we're dealing with low voltage so we can 'fudge it' using alternate less expensive materials (such as shrink tubing and common silicone adhesive/sealant instead of a plastic can filled with high voltage epoxy. It would never get past a county/city inspector for residential/commercial high voltage wiring. But being low voltage it doesn't need to. It just needs a bonded seal.

[bob850]

Just another option for replacing a failed OE or Ramac cable:

My cable went bad on my 99 V70, so I found a Deka cable #00282 at the parts store that was exactly the same length and worked great with a little bending on the battery end eyelet to make it a 90 degree. At the starter end, no modification was needed. The Deka cable I got in the store is a 4 gauge "switch to starter cable", but I found later that they also make a 2 gauge version (model #00377) which is easily found on ebay or other sources.

What I did was put one of those universal marine terminals like this one: https://www.napaonline.com/en/p/BK_7511031

I had to drill out the hole on the B+ cable end so it would also fit on the terminal, but other than that, it was very easy and a clean looking install. Less than $15 in parts. Voltage at terminals is up over 14V now. Would be even better if I got the 2 gauge cable version.

IMG_6432[1].jpg (43.83 KiB) Viewed 2908 times

[jreed]

Good work -- that looks nice and clean! Thanks for sharing this solution.

[theWIFES_S70]

Has anyone tried battery cables from BatteryCablesUSA?

The 30" version of this is coming in around $17...

https://www.batterycablesusa.com/0-gaug ... le-1-0-awg

I'm thinking this is the way to go...

Anyone have the lengths and the gauge of the other cables?

[bmdubya1198]

I used bob850's method today on my V70R and it's probably the cheapest and easiest solution! My original cable was very corroded just below the lug on the battery and it was so bad that the cable didn't flex at all for that first inch.
I was able to get both the marine terminals as well as a 4 AWG 40" switch-to-starter cable at AutoZone, about $15 for both. The 40" cable is the perfect length, I ran it through the factory routing within the harness covering (yeah yeah, it's easier to zip tie it to the covering and not tear into it, but I'm a perfectionist and like a tidy engine bay). It's a black cable, I would have preferred a red being that it's the positive side, but I know I won't ever mix them up.

I'm going to double check voltage at idle tomorrow, but it seems to have solved my ECM-912A code for ETM/ECM communication.