Talon differential won’t stay engaged

[All_Moto]

2020 talon with a turbo. I’ve had the hess bypass for long time, and had the torq master locker since they came out. Haven’t rode it a lot, first trip all was good. 2nd trip noticed front diff wouldn’t engage till the rear tires spun quite a bit. Today went riding on ice. The diff wont engage till hard acceleration and once it does engage, it quickly engages and disengages over and over. Not sure what’s it’s deal is. Any ideas?

 

[PaulF]

• Make sure you have a good power source to the Hess bypass switch.
• Make sure the Hess switch is working properly.
• Make sure the 2P connector is secure on the front diff clutch.
• Try the old i4WD switch (it should still work with the Hess bypass as long as the relay is still there). This will also turn on the electronics and throw codes if it detects any problems.
• If all that fails, you probably have a bad 4WD clutch.

 

[All_Moto]

• Make sure you have a good power source to the Hess bypass switch.
• Make sure the Hess switch is working properly.
• Make sure the 2P connector is secure on the front diff clutch.
• Try the old i4WD switch (it should still work with the Hess bypass as long as the relay is still there). This will also turn on the electronics and throw codes if it detects any problems.
• If all that fails, you probably have a bad 4WD clutch.

The diff reacts the same with the hess switch and the factory switch

 

[PaulF]

The diff reacts the same with the hess switch and the factory switch

OK, a few more tests before we condemn the 4WD clutch.

• Check the ground at the clutch motor, make sure you have a good ground. Any more than an ohm or 2 and you need to fix that first. If you had to fix the ground, test drive again.
• With the ground confirmed or fixed and still not working, completely disconnect the Hess bypass and hook it up back stock and try i4WD like it came from the factory.
• Go out and test drive for a bit. If it works, the Hess bypass has a problem. If it still doesn't engage, see if the i4WD light is on and/or it has stored any codes.
• If not working and still no codes, most likely the 4WD Clutch.

 

[All_Moto]

When I was out, the i4wd light would come on with either switch. Where exactly is the clutch grounded? I’ve never seen or heard of anyone having any trouble with the diff clutch

 

[HondaTech]

When I was out, the i4wd light would come on with either switch. Where exactly is the clutch grounded? I’ve never seen or heard of anyone having any trouble with the diff clutch

Ive replaced one that had failed for whatever reason.

 

[All_Moto]

I unhooked the hess bypass, and using only the stock switch now. No 4wd. I4wd light stays on. Even when resetting, comes right back on

 

[SLOWPOKE693]

Ive replaced one that had failed for whatever reason.

I'm like 99.999% sure that mine is on its way out or already broken. After the crash last season that broke the front diff the clutch started acting funny and would disengage at random times. Last time I drove it before pulling the engine out I had it in 2wd and it felt like it was in 4wd. I need to pull it out and see what's going on.....

Anyone see a market for a kit that replaces the 4wd clutch and makes the car full time 4wd? It wouldn't take all that much to replace the front clutch assembly with a chunk of billet aluminum that houses a bearing with a machined shaft through it that engages the diff splines on one side and has the appropriate yolk for the driveshaft on the other side. Could either have the kit come with a new longer driveshaft or give the end user the option to lengthen their stock shaft. Thoughts?

 

[PaulF]

When I was out, the i4wd light would come on with either switch. Where exactly is the clutch grounded? I’ve never seen or heard of anyone having any trouble with the diff clutch

You need to solve the i4WD light first. Even thought you don't use that system, there are many components that are used by multiple systems. The ground goes to a block under the hood and then from there to a bolt under the seat. If any of that ground circuit is bad, multiple things can be effected, stop working and throw codes.

I unhooked the hess bypass, and using only the stock switch now. No 4wd. I4wd light stays on. Even when resetting, comes right back on

If you are truly resetting the i4WD codes (not just the PCU codes) and the light comes right back on then you have a hard failure and it should be easy to track and fix. You do not need any special equipment other than DVM and a shop manual. If you don't have a shop manual, I suggest you get one.

Have you retrieved the codes? If not, here is the procedure using the i4WD lamp in the dash...

 

[SLOWPOKE693]

I unhooked the hess bypass, and using only the stock switch now. No 4wd. I4wd light stays on. Even when resetting, comes right back on

Do you have a way to directly apply 12v and a ground to the clutch assembly wires and drive it like that? That would eliminate a wiring harness problem and tell you for sure if the clutch is bad.

 

[All_Moto]

Do you have a way to directly apply 12v and a ground to the clutch assembly wires and drive it like that? That would eliminate a wiring harness problem and tell you for sure if the clutch is bad.

So I unhooked the green connector at the diff. Used a power probe, says it has a good ground, and switch sends power to the correct side. Even when grounding the diff side, and applying power with power probe, still nothing

 

[SLOWPOKE693]

So I unhooked the green connector at the diff. Used a power probe, says it has a good ground, and switch sends power to the correct side. Even when grounding the diff side, and applying power with power probe, still nothing

Check the resistance (ohms) between the two wires on the clutch side. It's an electro-magnet similar to an automotive A/C clutch and if it shows "open" on your meter it's definitely toast.

Mine makes an audible click when I apply power to it. Well, it used to until I broke it. 😆

 

[All_Moto]

Check the resistance (ohms) between the two wires on the clutch side. It's an electro-magnet similar to an automotive A/C clutch and if it shows "open" on your meter it's definitely toast.

Electrical stuff is not my strong point. I have an ohm meter, but don’t know how to use it lol

 

[SLOWPOKE693]

Electrical stuff is not my strong point. I have an ohm meter, but don’t know how to use it lol

Put the meter on the ohms setting and stick one lead on each of the clutch wires. If you get no reading it's "open" and if it's good the meter will read xx.xx ohms.

 

[All_Moto]

I’ll go check it now

 

[SLOWPOKE693]

@HondaTech, do you have access to any exploded diagrams or internal pictures of that clutch assembly? I know it's sold as a whole unit from Honda but was hoping maybe you had access to stuff us common folk don't get to see. 😁

 

[All_Moto]

Put the meter on the ohms setting and stick one lead on each of the clutch wires. If you get no reading it's "open" and if it's good the meter will read xx.xx ohms.

When hook it up, starts at 00.0 goes to 04.8

 

[All_Moto]

With the stock switch connected, key on, I get one long light, and 2 short lights, and one long light and 4 short lights with the i4wd

 

[PaulF]

With the stock switch connected, key on, I get one long light, and 2 short lights, and one long light and 4 short lights with the i4wd

Those are codes 1-2 Front Right Wheel Speed Sensor Abnormalities and 1-4 Front Left Wheel Speed Sensor Abnormalities.

Did you by any chance turn the key on with some wires disconnected? If so, that will set codes without even starting the machine or driving. it.

 

[All_Moto]

Those are codes 1-2 Front Right Wheel Speed Sensor Abnormalities and 1-4 Front Left Wheel Speed Sensor Abnormalities.

Did you by any chance turn the key on with some wires disconnected? If so, that will set codes without even starting the machine or driving. it.

Yes, I had the green connector apart when checking that the switch was sending power to engage the diff.
Switch is sending power. Still no 4wd.