RESOLVED: Headlight Issue - High Beams, but now low beams, through IPF Harness - Bad Relay (1 Viewer)

[RWBeringer4x4]

RESOVLED. For the "TLDR" folks looking for ARB/IPF Relay Part Numbers - here are two from Hella:

Hella 931680011 - Sealed Unit, Changeover Relay - Harness Requires 1. Replaced ProQuip P2512X
Hella 007791011 - Non-Sealed, Normally Open 4-prong relay (we will see how long they last). Harness Requires 2. Replaced ProQuip P1512X

Hi Everyone,

A couple of weeks ago while troubleshooting an electrical issue, I lost my low beam headlights. I'd put a substantial drain on the battery, but not enough that I couldn't start the FJ40. Oddly enough, after running the engine for a few minutes (presumably charging the battery a little) the headlights miraculously decided to start working again. So I just let it lie. I'm aware NONE of what I just wrote makes any sense from an electrical standpoint. Fast forward to yesterday - I just pulled the dash, put in a new speedometer cable, and replaced my dashboard lights with LED's. I also put a new LED in my headlight switch. I put everything back together, and once again, I have no low beams. This time, it doesn't seem like they're coming back on their own.

I found this post and have been trying to troubleshoot, but I'm sort of at a loss: Pull head light switch '78 FJ40

Based on the chart below I have taken a look at the voltage across the steering column switch terminal per figure 12-12. The "HL" terminal has 12V when the headlight switch is in the second position, so I believe I have proper low beam voltage.

HOWEVER, if I push the stalk forward to activate high beams, I don't see the voltage "swtich" to HU, but I'm not sure I'm supposed to?

To further confound things, I also have the IPF harness, and H4 headlights. The IPF harness makes use of 3 relays before it goes to the headlights, so I'm wondering if one of the relays went bad. Is there a good way to directly test a relay? I'm not entirely sure where to go from here.

To summarize Diagnostics so far:

- I have parking lights in the first pull position of the headlight switch. I also have functional dash and dimmer (lights get dimmer/brighter when I rotate the headlight switch.
- In the second pull position (switch all the way out) I have no low beams. BUT if I push the stalk forward, the high beams activate as they should.
- Confirmed 12V switched voltage from headlight switch on terminal HL, above. Neither HD nor HU appear to have voltage regardless of position but I may not be looking in the right place.
- Confirmed I have a full 12V power to the correct terminals at the end of the OEM headlight harness - ie: when I have low beams on, I have 12V at one terminal, if I switch to high beams, I have 12V at the other terminal.
- Grounds are shared between high and low beam and most of the grounds have been repaired/upgraded in the last couple years, so I don't expect there's an issue there.
- Both low beam filaments are intact, the bulbs aren't burned out.

So everything seems to work as it should, minus the low beams, and it seems like everything on the OEM (non-IPF side) is getting 12V as it should. That said, I accidentally plugged the IPF harness back in while the headlights were still "on" and I can hear at least one relay move.

This seems to point to the IPF harness or one of the relays, does it not? I'm not entirely sure how to check a relay for functionality or appropriate voltages. Any tips here? More importantly - does IPF sell replacement relays if this one is bad? Is there a better relay manufacturer I should be considering as a better replacement?

 

[RWBeringer4x4]

Ok all so I think I've answered my own question and found my problem.

One of the two ProQuip P1512X relays in the IPF harness is fried. The relay has a single P2512X relay and two P1512X relays. I figured I'd chance it and swap the two 1512's, and sure enough, now I have low beams but no high beams. Proof is further evidenced by the fact that the bad P1512X relay literally has crap rattling around inside of it.

So my next question is - can someone decipher relays and help me find a viable alternative? Looks like ProQuip is an Australian brand so their reach in the US is a bit limited. Further, given the relatively short lifespan, I'd love some input into a better/more reliable relay manufacturer. Bosh maybe?

From PROQUIP's Website - this is the relay that failed:

To create further confusion - this is the other part number for the third relay in the harness:

But the one in my truck is a 40/20A, not a 30/20A (and the picture shows 30/15A with the same part number). Clear as mud...

Also not clear on the difference between normally open, and changeover relay. So if there's anyone who understand electronics out there reading - I'd appreciate some input!

 

[RWBeringer4x4]

So I THINK Bosch makes some viable replacements, but naturally that would be way too easy. Looks like everywhere I know to look doesn't have these particular relays readily available either - 5-6 week shipping times. I'll check the local Auto parts places but these seem like the might be oddball relays, at least in the US...


This looks like the right 40A, Normally Open relay, but it's missing the center pin. Looking at the harness this plugs into, it appears the center pin is unused anyway, so I'm wondering if it makes a difference...

For the changeover relay, it appears the center pin IS used. This looks like the correct configuration (I think)

Anyone have any good parts houses to search for this kind of stuff from? Or any feedback as to who makes a good, durable relay?

 

[B y r o n]

I can't find the shop I was using when I needed relays and sockets, so sorry for that. What you have are standard 5-pin relays. So any standard 5-pin relay should be able to replace the one that is faulty. What I would suggest is that when searching for your replacement is that you use a "sealed" relay. As the term implies, they are sealed to prevent moisture from getting into the internals which will cause an early demise. You just need to make sure the amp rating is the same and that it is the same configuration, normally open or normally closed, with regard to how they react when power is applied.

 

[RWBeringer4x4]

I can't find the shop I was using when I needed relays and sockets, so sorry for that. What you have are standard 5-pin relays. So any standard 5-pin relay should be able to replace the one that is faulty. What I would suggest is that when searching for your replacement is that you use a "sealed" relay. As the term implies, they are sealed to prevent moisture from getting into the internals which will cause an early demise. You just need to make sure the amp rating is the same and that it is the same configuration, normally open or normally closed, with regard to how they react when power is applied.

Thanks @B y r o n - I’m surprised ARB/IPF wouldn’t provide sealed relays from the getgo - but the whole harness block these plug into is wide open anyway so I guess that’s not too surprising.

I haven’t seen anything advertised as “sealed” though admittedly my day job got in the way.

Are they obviously different looking at them from the outside?

 

[rkymtnflyfisher]

Have you checked Waytek?

 

[rkymtnflyfisher]

Electromechanical Relays, Resistors and Connectors | Waytek

Electrical Relays and Resistors from Waytek come in a wide variety of styles to meet all of your electrical wiring needs. Shop Waytek today!

www.waytekwire.com

 

[RWBeringer4x4]

One other question - if the center pin is “blank” (if nothing connects to it on the harness side) does it still need to be present on the relay? Could I presumably replace a 5-pin relay with a 4-pin relay (assuming amperage and everything else matches) if the missing pin is unused?

 

[B y r o n]

Sealed relays don't really look any different than non-sealed relays. If it doesn't specifically say it is a "sealed" relay than more than likely it is not.

If I remember correctly you can use either a 4-pin if that is all that is needed or if you have an extra 5-pin relay you can us it in place of the 4, just one pin isn't used.

 

[RWBeringer4x4]

Sealed relays don't really look any different than non-sealed relays. If it doesn't specifically say it is a "sealed" relay than more than likely it is not.

If I remember correctly you can use either a 4-pin if that is all that is needed or if you have an extra 5-pin relay you can us it in place of the 4, just one pin isn't used.

What I have is the exact opposite - the relays that came with the harness are 5 pin but as far as I can tell the center terminal isn’t being used.

So I’m guessing the opposite applies as well...

 

[B y r o n]

With regard to testing relays you might want to watch this video:

 

[John McVicker]

Yes, if what you were using did not utilize the center pin (87a), then you can purchase a 4 pin relay to do your job.

 

[RWBeringer4x4]

So I'm browsing Waytek at @rkymtnflyfisher recommendation - definitely some options there but I'm just winding up further down the rabbit hole.

For example:

This seems to fit the bill as a viable replacement - it's a sealed unit like @B y r o n recommended, can handle temperatures to about 250F, which should be OK in the engine bay, and it's 40A, just like the broken relay. BUT

1. It appears to be Single Pole, Double Throw (not sure if this would matter, or what the one I pulled out is).
2. It also has a 30A normally closed rating so I'm not sure what that means either
3. Further - the main relay that came out is labeled as a "changeover relay" with a double amp rating (40/20A) and I don't see anything specifically called a changeover relay on Waytek's site (though there are a few with double amp ratings) - including this one.
4. The changeover relay I have (still works) is a 40/20A changeover. If I were to put in the 40A (open) and 30A (closed) relay below, would it work with a 40A/20A changeover relay? Or would I need to replace the changeover with a 40/30?

I guess what's most confusing is I'm not sure how or why this 3 relay setup is used. I'm guessing the relays are to increase the current to the (more powerful) H4 headlights, and I assume the changeover relay is there to "pick" between high and low beams depending on the dash switch positions, but I really am not clear on how relays interact.

For example - this looks to me like potentially a similar 40/20A changeover relay at first glance, but it makes no mention of "changeover" (nothing on the Waytek site does) and I'm also not sure it would work with the 40A above. There are also 20/40A relays, and I'm not sure if they differ from 40/20A relays.

I've thoroughly confused myself.

 

[rkymtnflyfisher]

SPST, SPDT, DPST, and DPDT Explained - Littelfuse

www.littelfuse.com

 

[B y r o n]

I'm going to send you further down the rabbit hole with this information.

Additionally, I don't know if you saw the technical information on the relays you are dealing with.

 

[rkymtnflyfisher]

I guess what's most confusing is I'm not sure how or why this 3 relay setup is used. I'm guessing the relays are to increase the current to the (more powerful) H4 headlights, and I assume the changeover relay is there to "pick" between high and low beams depending on the dash switch positions, but I really am not clear on how relays interact.

Without looking at a wiring diagram it is hard to determine what is going on with this one.

 

[RWBeringer4x4]

I'm going to send you further down the rabbit hole with this information.

Additionally, I don't know if you saw the technical information on the relays you are dealing with.

The second chart I've seen - that's what I'm using to try and find an appropriate replacement.

I think I understand poles and throws, but since I don't have a wiring diagram for the ARB harness, I'm not entirely sure which setups will or won't work. That's why I'm just trying to match what I have. However, the technical information from the ProQuip website is missing a lot of critical details about the relays so it's tough to identify an apropriate alternative.

 

[Shark56]

Rick, I dont know if you get up towards Wilmington much anymore but Pasco, Battery Warehouse, usually has a bunch of different relays.

 

[RWBeringer4x4]

Rick, I dont know if you get up towards Wilmington much anymore but Pasco, Battery Warehouse, usually has a bunch of different relays.

Good to know! Wilmington isn’t far and I’ll be up that way for work on Thursday. Maybe I’ll drop in. Never heard of them before - looks like they’re just over the river on 13?

 

[B y r o n]

The second chart I've seen - that's what I'm using to try and find an appropriate replacement.

I think I understand poles and throws, but since I don't have a wiring diagram for the ARB harness, I'm not entirely sure which setups will or won't work. That's why I'm just trying to match what I have. However, the technical information from the ProQuip website is missing a lot of critical details about the relays so it's tough to identify an apropriate alternative.

You need to click on the Technical Information tab and then compare the diagram on the side or your relay and part number to see exactly what function the relay is. This will give you the information to choose the proper replacement part.