Installed Blue Sea 7622, now van won't start

[gordon]

I recently replaced my ailing Sure Power 1315 with a Blue Sea 7622 as described in https://www.sportsmobileforum.com/fo...0&d=1662043356

My 06 diesel had the Sure Power wired with assisted start and I wired the 7622 with start isolation. I reused the wire connected to the Sure Power start assist terminal and connected it to the Blue Sea brown wire (isolation #1). Wiring to Blue Sea is house battery to terminal A, starting batteries to terminal B, ground to ground buss bar, and isolation #1 to the wire used for the Sure Power start assist. Ground has a 10a fuse, isolation #1 has a 2a fuse.

With the Blue Sea yellow switch in the remote position and the inner button not depressed, the van started without issue. However, when I tested the voltages at the Blue Sea A and B terminals, it didn't seem that the house battery was being charged (e.g. starting battery at around 14v, house battery at 13v). Turned off the van and scratched my head.

Thinking that I perhaps misunderstood the yellow switch, I set the switch to remote with the inner button depressed. When I tried to start the van, I hear a dreaded sparking sound, the dash goes dead, and no joy on starting.

The yellow switch is now in the lock off position. With the ignition key in the accessory position, things seem to work as expected. Radio, power windows, head lights all work. However, with the key in the on position, none of the above work and do the dash gauges and lights don't work. Key to start is same as on with the added joy of no starting (no clicking sounds, just a very depressing silence). There also seems to be a steady drain oh the starting batteries (voltage has dropped from 12.5 to 11.7 in half a day with no apparent draws). I've disconnected that starting batteries to try to preserve them.

All house battery stuff (lights, inverter) works as expected.

Anybody have an ideas what I fried by trying to start with inner yellow button depressed? At this point, it's looking like I'll have to have the van towed from my garage to the shop and make a contribution to my mechanic's new boat.

Thanks.

gordon

[Scalf77]

Not really understanding why, but being that the start assist line was hooked up. I would check to see if you have blown use F2.33 , I would also check F2.2 and F2.27. These could have been during when starting.

If they are blown I would remove the start assist line. That said it shouldn't no way blow up the circuit. Have you done any other work? Is house battery grounded to frame?

I will have to give this some thought, I don't see that anything was hooked up wrong. I got to ask if you are sure you didn't mix up the Black and Brown wire?

[gordon]

Thanks for the reply!

Those 3 fuses look fine. I also checked them for continuity with a multimeter. (F2.2 requires a fair amount of contortion to access.)

The black ground and brown isolation #1 wires aren’t mixed up, although that’s a mistake that’s right in my wheelhouse.

No other work was done and no changes were made to house battery. I’m not sure where SMB West grounds the house battery on an RB50. I’ve changed it a couple of times over the life of the van, but haven’t altered any wiring. Strictly a drop and replace.

It doesn’t look like SMB West tapped F2.33 for the start assist. Not quite sure where the start assist wire goes, it disappears into the floor on our RB50. Once things are fixed, I plan on just pulling the 2a fuse on the brown wire. I don’t think we really need the start isolation.

[Scalf77]

The connection for start assist is done usually in the steering column, not to hard to get at. It should look like this .



Yes, you don't need start isolation. I still can't think anything that should cause that.

I would start checking for voltage at those locations when the key is in the state.

[Nrobert10]

Where are you located?

So on the 7622 all really needed to operate it is battery connected to both side of the relay and the ground wire(black) from the remote switch wiring tail.

If you disconnect all the wires besides the black and your two battery leads can you get your van to start with the ACR in disconnect locked position?

If not you have other issues now not related to the ACR.

I have the 7622 in my van but never ran the wiring to the switch, I manually engage the ACR if I need to jump start myself.

[gordon]

Thanks for the suggestions. I’ll keep digging.