Trouble installing PDM

[Advodka]

Ok, I'm hoping some of you that have done this can assist ton this. I installed my PDM that I finally received. Got a problem though. The new harness did not have a plug for the coil signal\ignition switch.:bang: It does have a brown and black plug for th ignition but it's separate from the coil plug wereas mine is all in one. So I got the old section off of my old harness and hooked it up that way. But here is my problem. If I take jumpers and connect the orange to orange and black to black for the switch, I get nothing. But I am reading 12V on the orange and with the switch on 12V on the black from the switch. If I turn the switch off the black goes dead, like it should I think, but I get no power to the bike. The orange wire from the new harness is reading 12V and if I just jump straight orange to black skipping the ignition switch I have full power and everthing works but my headlight dimmer. :bang::bang: Any ideas will be greatly appreciated.

 

[firedog19]

A black wire in a dc system is supposed to be a ground

 

[Advodka]

Ok. I agree on the blk wire situation. Problem that is stumping me is orange into the switch and blk out. I have figured out that by jumping them together what I am actually doing is grounding out the orange which is giving my bike the signal to turn on. Doesn't seem right to me but hey it's a bigdog so I'm asking. :bang: and if that is right, does that mean the switch grounds the system? By the way, fixed the headlight issue. Loose connection. If I can get this switch working I'll be in business.

 

[DRBarnhart]

Problem that is stumping me is orange into the switch and blk out. I have figured out that by jumping them together what I am actually doing is grounding out the orange which is giving my bike the signal to turn on. Doesn't seem right to me but hey it's a bigdog so I'm asking. :bang: and if that is right, does that mean the switch grounds the system?

Yes, the switch supplies a ground (not power) to turn the bike ON. It's called "ground switching" and seems to be what throws guys for a loop when troubleshooting.

Dennis

 

[Advodka]

So what do you think I should try? If I run a straight ground to the orange off the harness I get power but if I run it through the switch I get power out on the blk instead of a ground.:bang: How do I get my switch to throw a ground instead of letting the power go through? I tried putting a ground input to the switch but still nothing.:bang:

 

[Srodden]

I just did my 05 mastiff had to do something up there just can't remember can you show pics? . I remember the oil switch had brown black and I think the compression release had same. I re used the ignition yellow blue and red harness as it was not supplied . If you don't have all your grounds correct you will have issues. If you study the wiring diagram supplied real good you can trace your issue usually.

 

[Srodden]

Also ground to the battery as the battery box is not a good grounding source go right to battery.

 

[DRBarnhart]

If I run a straight ground to the orange off the harness I get power but if I run it through the switch I get power out on the blk instead of a ground.:bang:

It sounds like the black wire going to the ignition switch isn't grounded like it should be.

How do I get my switch to throw a ground instead of letting the power go through?

It should be a simple as the orange wire being connected to the PDM and the black wire connected to ground. That way when you turn the switch ON you've supplied the ground.

I tried putting a ground input to the switch but still nothing.:bang:

If you put a ground on the opposite side from the orange and the bike wouldn't turn ON it sounds like the ignition switch is bad. Couldn't have been your problem all along could it?....

Dennis

 

[Advodka]

Thanks for all the assistance guys. I pulled the coil cover and ignition switch and found a "jumper" installed on the switch wire.
Removed this and everything is working like it should. Thanks again for all the input.

Now somebody is going to tell me that if you remove that jumper the engine will lock up. :roll::roll:

 

[Advodka]

Did a quick search but didn't find anything. Since this jumper was the cause of a few extra hours of work, what was the purpose of the jumper from BDM?

 

[Newcityboy22]

I'm new here all I ever had was a neutral light on the 4 wheeler. What is a PDM and why are you switching it out?

 

[Advodka]

A PDM is one type of replacement for the EHC (brain) on the bike. BigDogs had problems with their EHCs and some of us had to replace them.

 

[Rex Winters]

I replaced my EHC with a PDM and didnt have this problem. I had a similar one with the horn relay, though, and wound up splicing them together to make it work. Made no sense, but it works and I rarely use my horn. I found out waving the gun around had a better effect :-D

 

[Srodden]

Thanks for all the assistance guys. I pulled the coil cover and ignition switch and found a "jumper" installed on the switch wire.
Removed this and everything is working like it should. Thanks again for all the input.

Now somebody is going to tell me that if you remove that jumper the engine will lock up. :roll::roll:

That is a circuit protection to help in the case of an electrical spike so the original ehc computer could survive the event. All it took sometimes was a spike and the original ehc was toast. Example getting a battery jump and arcing the cables. I spoke to BDM technician who builds the PDM modules he said remove it for PDM installation . You are correct

 

[Newcityboy22]

So on an 07 mastiff lets say, what lights should be on at idle and what lights should be on with key on not running and what do the lights on or off signify?

 

[DRBarnhart]

That is a circuit protection to help in the case of an electrical spike so the original ehc computer could survive the event. All it took sometimes was a spike and the original ehc was toast. Example getting a battery jump and arcing the cables. I spoke to BDM technician who builds the PDM modules he said remove it for PDM installation.

That makes no sense at all considering the ignition switch was only supplying a ground to the EHC in closed loop.

If information like that came from a "technician" building PDMs I may have to think twice before installing one...

I call bullshit!!!

Dennis

 

[Srodden]

That makes no sense at all considering the ignition switch was only supplying a ground to the EHC in closed loop.

If information like that came from a "technician" building PDMs I may have to think twice before installing one...

I call bullshit!!!

Dennis

If information came like that ? I always tell the truth whether the tech was right or wrong don't know. Calling bullshit on your part is pretty much a guess . It wasn't imperative to remove it for PDM installation he just suggested it as it was originally intended for the EHC . Just sharing what I know

 

[DRBarnhart]

If information came like that ? I always tell the truth whether the tech was right or wrong don't know.

Don't get me wrong Scott, I wasn't questioning you! It was the "technician" from BDPP that I'm having a hard time with. Apologies if you thought I was doubting you!

Calling bullshit on your part is pretty much a guess.

After working in electronics for 35 years I'd like to think it was at least an educated guess. :lol: How I see it the ignition switch has two wires both of which connect directly to the EHC. So, he's saying the jumper was installed to protect the EHC from the EHC?

Doesn't it seem like their time would have better spent coming up with a way to protect US from the EHC!!! :bang: :roll:

Just sharing what I know

Appreciated! It's what makes this forum what it is... :2thumbs:

Dennis

 

[Advodka]

Thanks Scott and Dennis, all seems well and bike is running great.

I think this is what you're looking for New city. :2thumbs:

 

[Brew]

So on an 07 mastiff lets say, what lights should be on at idle and what lights should be on with key on not running and what do the lights on or off signify?

So to answer your question!
1) When you turn your key on you will see all lights except for the PC linked light come on for about three seconds. This is the start up BIT check.
2) Then you should only see all lights extinguish except for two which will be the green controller on and yellow power LEDs.
3) When you push the run button on the right hand control the red ignition LED should light meaning shes ready to crank once you hit the start button.
4) These three LEDs (Yellow, Green and Red) should be on when the scoot is running and there will be blinking (I forgot which ones off hand).

I cant speak about the air ride system maybe someone with it on their scoot can let you know when that light comes on if you have it... Other than that, if you have other lights on, you may have a fault so look at the pic I attached, it should apply to your scoot if you still have the 07 EHC on your scoot...:2thumbs: