Fuse Block Relay Problem

[jwalt]

We are on the road with no dash air! I'm getting intermittent operation from the dash air blower, windshield fans, and mirror adjusters. I'm thinking it's the accessory relay. However, the leveling jacks work fine and come off the same relay/plug in harness. I'm not sure where to look. Freightliner said it's a common auto relay, go to NAPA and get one. I do not want to put my leveling jacks in jeopardy by doing something stupid. Any thoughts or ideas would be appreciated. 2016 Tuscany 42GX. The photo shows the black relay just about in the middle of the fuse board and the plug in accessory harness in the upper right. Thanks, Jeff

[lwmcguir]

I have the same coach and never had any issues so not much help that way

The hydraulic pump does have its own circuit breaker in the compartment on the feed wire

Curious if you're still having the dash issue?

If that relay is supposedly bad, I wouldn't hesitate to plug in a new one

[camperguy99]

I had similar problems with my 2015 Tuscany. There are two of the relays on the board. Both are wave soldered onto the board and you will need a solder pot to remove them due to large solder tabs on the bottom. . Or two or three hot soldering irons. I had a friend who worked for a large electronics company and he borrowed one that I could use. Pots are not too expensive on Ebay maybe $25-40.

[jwalt]

Originally Posted by lwmcguir

I have the same coach and never had any issues so not much help that way



The hydraulic pump does have its own circuit breaker in the compartment on the feed wire



Curious if you're still having the dash issue?



If that relay is supposedly bad, I wouldn't hesitate to plug in a new one

I pulled the harness plug and there are only seven pins, all seven from the relay. None of the stuff works. The relay light does not light up either.

[jwalt]

Originally Posted by camperguy99

I had similar problems with my 2015 Tuscany. There are two of the relays on the board. Both are wave soldered onto the board and you will need a solder pot to remove them due to large solder tabs on the bottom. . Or two or three hot soldering irons. I had a friend who worked for a large electronics company and he borrowed one that I could use. Pots are not too expensive on Ebay maybe $25-40.

I can't believe the relay is soldered in. Do I have to remove the entire fuse board to get it off? Thor just doesn't make it easy.

[OldWEB]

None of the stuff works. That is a broad statement, one that I take meaning the relay is not getting its 12V signal to operate. Have you confirmed the relay is getting voltage or confirmed the contact (there is only one) is not closing? Do you have a schematic or diagram you can share, may be some ideas floating out here.

One jumper temporarily installed could be all it needs to get you going.

[lwmcguir]

Originally Posted by jwalt

I can't believe the relay is soldered in. Do I have to remove the entire fuse board to get it off? Thor just doesn't make it easy.

Curious if yours was soldered in as well. I am not at my shop right now or I would check mine.

Whomever supplied the relay board might have a replacement board but if your still on the road you need a quick fix.

Call Thor and ask for info regarding the relay, and complete board, maybe some hope of getting something overnighted

[lwmcguir]

Originally Posted by OldWEB

None of the stuff works. That is a broad statement, one that I take meaning the relay is not getting its 12V signal to operate. Have you confirmed the relay is getting voltage or confirmed the contact (there is only one) is not closing? Do you have a schematic or diagram you can share, may be some ideas floating out here.

One jumper temporarily installed could be all it needs to get you going.

Good question for the OP, are we sure were getting power to the board?

[jwalt]

Originally Posted by OldWEB

None of the stuff works. That is a broad statement, one that I take meaning the relay is not getting its 12V signal to operate. Have you confirmed the relay is getting voltage or confirmed the contact (there is only one) is not closing? Do you have a schematic or diagram you can share, may be some ideas floating out here.

One jumper temporarily installed could be all it needs to get you going.

Good point on the power. I need to verify that. Fuse board diagram attached. I'm pretty green at electronic stuff so any advice is welcome.

[OldWEB]

Now we can guesstimate much better!
So it shows the K1 relay receives power on pin #8 on the J4 accessory plug.

Check that to ground for voltage. Also check the chassis battery terminal lower left for 12V, this ensures there is power to this panel and a good check that the meter works!

BTW, what is it that is 'spose to pick up the relay (apply power to pin #8)? I am guessing that there is no 12V here, cuz you said the LED did not light up either.


EDIT: looking at it some more, "Accessory" would be on when the key is "on" (unit running).

[jwalt]

Originally Posted by OldWEB

Now we can guesstimate much better!
So it shows the K1 relay receives power on pin #8 on the J4 accessory plug.

Check that to ground for voltage. Also check the chassis battery terminal lower left for 12V, this ensures there is power to this panel and a good check that the meter works!

BTW, what is it that is 'spose to pick up the relay (apply power to pin #8)? I am guessing that there is no 12V here, cuz you said the LED did not light up either.


EDIT: looking at it some more, "Accessory" would be on when the key is "on" (unit running).

I'll check those voltages asap. I assume K1 pin 8 would show voltage with the ignition on if all were normal, and that would power the relay. Right? [emoji848]

[jwalt]

Update. K1+ coil, pin #8, had no voltage with ignition on or off. The chassis battery terminal did have full 12v power supplying the fuse board. I guess I need to check upstream for a problem feeding K1 pin 8.

[camperguy99]

My problem with the Fuse Board was the relay stuck closed. Left some lights on always. I could tap the relay with the handle end of a screw driver and cure the problem. Yours seems to be stuck in the open position. I'd still give it a tap and see if anything changes. Fix was short lived as it would stick again after being cycled. Like I said before I replaced the relay but need a small solder pot to get the relay out of the board. I did buy two replacement relays and changed both. Think they were a bit more money than the automotive relay due to the high amperage required. About $20 as I recall?

Camperguy99
2015 Tuscany Class A

[OldWEB]

Originally Posted by jwalt

Update. K1+ coil, pin #8, had no voltage with ignition on or off. The chassis battery terminal did have full 12v power supplying the fuse board. I guess I need to check upstream for a problem feeding K1 pin 8.

This was checked with plug J4 inserted, right? Have you found a schematic of the coach wiring?


You could confirm with J5 #4, it should have 12V and pick up the "Ignition" relay below.

[jwalt]

Originally Posted by camperguy99

My problem with the Fuse Board was the relay stuck closed. Left some lights on always. I could tap the relay with the handle end of a screw driver and cure the problem. Yours seems to be stuck in the open position. I'd still give it a tap and see if anything changes. Fix was short lived as it would stick again after being cycled. Like I said before I replaced the relay but need a small solder pot to get the relay out of the board. I did buy two replacement relays and changed both. Think they were a bit more money than the automotive relay due to the high amperage required. About $20 as I recall?



Camperguy99

2015 Tuscany Class A

Currently on the road. I'll try a tap tap when we land tonight. Thanks for the info.

[jwalt]

Originally Posted by OldWEB

This was checked with plug J4 inserted, right? Have you found a schematic of the coach wiring?


You could confirm with J5 #4, it should have 12V and pick up the "Ignition" relay below.

Currently on the road. I'll check your suggestions asap. Thanks for the continued help.

[OldWEB]

So are the items working, intermittent or not at all? And the jacks you say they do work? The wire for the jacks is only fused at 5A so it must be part of the control and not affecting their operation, as you say they still work... odd.
What are you doing for A/C?

[jwalt]

Originally Posted by OldWEB

So are the items working, intermittent or not at all? And the jacks you say they do work? The wire for the jacks is only fused at 5A so it must be part of the control and not affecting their operation, as you say they still work... odd.
What are you doing for A/C?

Everything plugged into accessory J4 has not worked at all for several days. Except for the jacks control (5A) and the jacks, which have worked fine. To keep cool, we've been running the generator and roof air which keeps it tolerable. I'll probably try Thor again tomorrow to see if they offer up anything helpful.

[jwalt]

I re-checked the fuse board today. Everything related to J4 and K1 relay still no workie and no voltage. I also tapped the relay a little and didn't hear any clicks or any indication it was doing anything. I also checked J5 pin4, all OK, 12 volts, normal.

The brown wire from J4 pin8 K1 disappears into the wire loom. I need to trace it out and find the transition to the Freightliner wiring. Then up to the ignition switch which is red, blue, green, and yellow wires. And or check continuity or other reasons why there's no voltage at J4 pin8. At least that's how I'm seeing it. Thanks again for the continued help. I certainly appreciate it.

[OldWEB]

You need a schematic or wiring diagram or someone that has an idea where the wire is from, beyond my knowledge.
All I can SUGGEST is to bare the two ends of a short piece of wire and jam it into J4 #8 and the other end into the wire of connector J5 #3; That way the wire is fused at 5 amps and if the brown wire circuit is faulty (J4 #8 - grounded) it will only blow a 5A fuse (F28). Jumpering this should pick up relay K1 when the ignition is "on".



This is ONLY a suggestive idea, something I would do (or similar) to keep going down the road. You do need Thors/Freightliners help with a schematic.