85 GL12LTD will not start

[supertune]

I am working on an 85 GL1200LTD with CFI injection. Local Honda dealer would not work on it, so the owner asked if we (I run a shop "SuperTuneMotorsports.com" in Denver area) could look at it.
Motor will turn over, but has no spark. Fuel pump does not turn either.
Traced back to the Ignition Control Module (computer) box behind the seat; the LEDs that should come on for self-test do not. It looks as if the ICM has no power or is dead.
I am trying to determine if there is voltage getting to the ICM, but can't get to the pin (should be #21) to see if there is input power (12v). Any one know where the 12v line goes into the harness to the ICM? I would trace that back to check input power.

A local Honda dealer that is friendly with us is looking to see if the ICM is still available. The price is $1600 if it is!!!
Bottom line is that I want to be sure the ICM is bad BEFORE I suggest the owner spend the BIG bucks for one (IF Honda can get one).
If anyone has any suggestions about validating the problem is the ICM or anything else, I would appreciate it?
Thanks!
mike

[pauln]

I am trying to determine if there is voltage getting to the ICM, but can't get to the pin (should be #21) to see if there is input power (12v). Any one know where the 12v line goes into the harness to the ICM? I would trace that back to check input power.
Thanks!
mike

Mike, you can take the connector at the computer apart. Disconnect the connector from the computer, cut the plastic tie that holds the rubber boot, pull back the rubber boot and remove the screw on the end of the blue plastic connector. Then you can slide the connector apart sideways. You can then reconnect the connector to the computer and get at the pins from the rear of the connector (just watch you don't short out anything).

There is a schematic and 85 LTD supplemental manual available (free) at <!-- m --><a class="postlink" href="http://goldwing.soylentgeek.com">http://goldwing.soylentgeek.com</a><!-- m -->

Let us know how you make out.

There are several experts on these models - I am getting there, but have a long way to go. Some real experts like Oregonwinger should be along to give you more tips.

[roscoepc]

Welcome to the Site!!

This might seem like a silly question but is the kill switch set to the run position and if it is, is there voltage going to it? What you've described, engine turning over but no spark and no running fuel pump, fit's that to a T! If you need to know any fuse locations, let me know and I'll look them up for you.

[supertune]

thanks for the replies.
i did find that the boot over the large plug for the box does come off to check the pins. i do have the schematic and Honda manual supplement for the LTD. there is no power to the pin on the ICM so i don't think that the box is bad.
it does make sense that there is some other reason; loose wire, dirty connectors, contacts on the kill switch,... that is causing the problem. this bike is in excellent condition and appears to have been well and professionally maintained.

with ironic timing, the owner stopped by yesterday to check on progress right after i sent this post.
he said that a friend had ridden the bike this past summer (he has had recent back surgery, but is looking forward to riding next year) and it had starting problems; would turn over but not start. after several attempts, and some prodding around, he got it started, but it has not run since he got it home.
we did check and clean every connector, but i will double-check these and the kill switch contacts today.
thanks for your tips and ideas.
m

[supertune]

It took sitting down and really cutting through the jungle that is the electrical systems in the LTD.
I had to really trace through where all the connections go, but.... it turned out to be the simplest thing it could be: One of the 30amp fuse-links near the battery had a small crack in it.
The 30a link to the starter was OK, the other one (that feeds the rest of the ignition system) metered ok when we first checked it, but had a small crack and was the problem.
Rather than replace a $1600 ECU (which would NOT have fixed the problem!) diligent troubleshooting paid off and we replaced both $.96 cent links (just to be sure) and everything works fine!

[William_86]

congratulations dude

[eurowing]

Those cheap fuses are horrid. I recommend you splice in standard auto fuse holders and replace them both.

[roscoepc]

Glad it turned to be so simple!! If I'da been thinking I would of suggested looking at the dogbone fuse first as they have a tendency to crack with age.

Now if you want to really be a Superhero to your customer check the three yellow wires coming out of the stator and see if that connector by the battery has been cut out and hardwired together. If it hasn't been cut out, recomend to your customer that it be done because that connector will get hot enough to burn the spade connectors causing possible regulator or stator failure. Also those same three yellow wires need to be soldered at the regulator also, which is a little more of a pain as the seat and the fake fuel tank has to come off, but worth it in the long run.

Have fun with it and tell your customer about Vic's Site here!!

Good luck!

[al smith]

Does anyone have the Bob Kekies pages on LTD-SEI repair? I have them but it looks like he may have shut down or moved to another srver? Al Smith Thanks