Title: 4 Wire DESS - Black with Purple Tracer

[Darboy]

Ski: 2007 GTI 130 Nothing fancy just the way it was out of the wrapper.
Problem; Intermittently does not get the 2 beeps needed to start. (Fails more times than it works)
Observations when it fails.

• Depress the Start/Stop Button with no key. No instrumentation every time.
• Place key on post. No lights and no beeps. Depress the Start/Stop button, does not start and no double beeps and no lights on the instruments.
• Take the key off and on the post, give it a twist or two, maybe a cuse word or two and then out of the blue for no reason we get two beeps the ski starts and does stop till we depress the start / stop button or remove the key.

Have had issues for several years but never was so bad that we could not get the ski to start. But now it is getting bad to the point where I don’t trust it. Lake MI is not a small pond and there is not always someone around for a tow.

First made sure I was working with the correct service manual. I had the 2007 downloaded but reading the intro it clearly states that it is for a 2006. Well a 2006 has a 3-wire DRESS and an MPEM. The 2007 has a 4-wire 2 reed switch DESS post and NO MPEM. So downloaded the 2008 and it has the correct wiring diagrams. (Just a heads up.)
So this is where I am at.

• Battery excellent
• All connections are tight.
• All fuses check good.
• Replaced 30 amp relay no change. (This was a SWAG)
• Completed all continuity checks for a 4-wire DESS post. On the last check, we are looking for 0 ohms between the BL/PU wire and the BL wire with the lanyard on the post. I never get this reading it is always open.

This is the dilemma, continuity test is solid (always open). However, messing around with taking the lanyard off and on will allow it to be read and the ski comes ready to start, and not sure why. Using the wiring diagram I can trace the BL/PU wire back to 30 AMP relay and then I believe it goes to the ECU from there.

So here is the question, given the sequence to complete serial number validation to get two beeps to allow the instrumentation to come on and allow the start circuit to energize to allow starting what function does the PU/BL wire serve? Also appreciate some feedback, replace DESS Post, continue to look for a bad ground or short or chase the start-stop switch circuit since it does play a roll in allowing the energizing of starting sequience.

 

[ski-d00]

If you have an open circuit on the DESS post with key on then you either need a new key or a new post. Try your spare key.

Depress the Start/Stop Button with no key. No instrumentation every time.

This is normal for your year/model. Only the older and newer skis wake up when pressing the start button.

Place key on post. No lights and no beeps. Depress the Start/Stop button, does not start and no double beeps and no lights on the instruments.

Just like not putting the key on. So either bad connection or bad post or key. Have seen lots of both.

 

[Darboy]

Thank you ski-d00 for your feedback. I do have an open circuit between the Bl/Pu wire and Bl coming from the post with the key on. This must be from the second set of reed switches in the post. And it is open solid yet from time to time something happens and I get two beeps. Now this would make since IF that reed switch does not need to be closed while the ski is running. Do you or anyone else know how that circuit works once the switch is made. It goes to the 30 amp relay and does???????? And does it interact with the stop/start switch?

 

[ski-d00]

The Black and Black/Purple circuit at the DESS harness is what supplies power to your ECU to wake it up as soon as any key is put on the post and has to be 0 ohms with the key on. It will never run at all with this circuit open. It doesn't have to be the correct key which is what the other circuit checks for the matching code of the chip in your key. It does not interact with the start/stop switch, separate circuit to the ECU that activates starter.

The way the posts typically fail is exactly how you describe. They will start to not recognize putting the key on sometimes and the key will have to be removed and put back on. Eventually, it won't recognize it at all.

 

[Darboy]

This is an awesome update. Again, thanks ski d00 for your feedback, much appreciated! There is a shop that has a post in stock and will be picking it up on Saturday. Hopefully will get installed next week between household chores and putting brakes on my son's car. Since you have placed many and I have not placed any if you have a trick or 2 to share that would be great.

 

[ski-d00]

To confirm that your post is bad, you should first try a different key to see if it wakes up. Next, put a jumper at the harness connector between the black and black/purple and see if it wakes up. You can also connect the white/gray and black/yellow wires at the connector to the 2 contacts in your key which will then allow the ski to start and run completely bypassing the post.

When I change posts, I'll either replace the entire harness with one I already have or buy one on ebay cheaply or I'll remove the terminals from the connector and fish the wires through the harness sheaths then crimp new terminals on the wires and put back into the connectors to recreate the harness assembly exactly as OEM. Of course, nobody else ever seems to do this. What they do is cut the wires just after the post and use butt connectors which works fine as long as they use waterproof heat shrink connectors and ideally soldier each wire connection. Doing it this way makes it simple and fast since all you wil need to do is separate the steering housing and do it while sitting on the seat.

 

[Darboy]

Thanks for the follow-up... much appreciated and the dialog is awesome. So once you advised that the function of BL with PU tracer from the post I was comfortable with jumpering it out and did complete a failure validation. And as you suspected and advised it is a bad post. So since I am the type that really hates doing things twice I normally will use OEM parts unless someone advises me of a better solution based on experience. I do this since most parts are engineered and manufactured to specifications and design. It is always possible that the manufacturer of a component can sell / distribute product sold to the OEM, but that is rare. But open to suggestions if you have one. As for installing, I would be lying if I did not say I thought about using butt connectors with solder and shrink-wrapped. I have fixed many trim and tilt indicators for merc-cruiser stern drives with them. However, I have read a ton of posts here that report fishing the wire through is fairly easy but I never was handy at putting new terminal ends on and getting to fit back in the connector. I think that is an art all by itself. So as far as installing the new post I will wait till I get the new post and look at the job at hand and make a decision on what I going to do then. Please know I really appreciate your feedback. Lastly the key. I knew it was not going to be the key, I have 3 of them and did not believe that all 3 could be bad. In addition, I did see a post here on the forum that suggested validating the key through a resistance check. I did run that check on all 3 keys. All 3 had about the same level of resistance, well under 10 ohms. I no longer have the link to that post but adding the verbiage below:
There are a few things you can do to test the key itself, clean it first with a Q-tip dipped in alcohol and make sure the two sides and one top contacts are in place and clean.

You should see continuity between both of the ground contacts in the side body of the key, and using the red test lead on either of the side ground contacts and the black test lead on the top center contact you should see less than 10 ohms of resistance on the IC serial chip.

I find any more than 10 ohms on the IC chip usually causes intermittent or complete failure of the key to work properly with a MPEM module, my shop version of Cardeo Pro will read keys up to about 20 ohms of resistance and program them to modules every time but the MPEM won't recognize them reliably in normal operation.

Thanks again for your assist.... much appreciated

 

[ski-d00]

Most people that say it is easy to fish the wires through the steering column usually have older skis before they made complete wiring harnesses for the steering column without sheaths that are divided into several paths. It can be done but I would not say it is easy for your type. I usually pull the entire harness out and work on it on the bench.

 

[Darboy]

Last update... we did complete the repair today and the post replacement did resolve the issues with getting the ski to start every time the safety key was put on the post. Understand the function of the black with the purple tracer was a big help. After studying the repair actions needed to install I decided that splicing may not have been the right way but it was the easiest and quickest way. I used butt connector with solder and shrink tubing. I also had nylon wire sheath that I used to protect the wires since it was now a bit longer. In addition I did use an OEM post purchased from a locally dealer.

Many many thanks to ski-d00 for all his assist on this.