Hard to find diag port on my 102C3

mh0pe · October 04, 2020, 11:06:24 PM

Hi! I own a '91 102C3 and through multiple mechanics and hours of searching...I can't find the dang DDEC DDL port. Not under the dash, not behind the steering column, nothing of note in the driver side front junction box. I've also looked around the engine, checked the rear junction, and the traced most of the cabling but came up short. Any ideas y'all?

buswarrior · October 05, 2020, 04:55:07 AM

Look up, in the baggage bay...

Yeah, strange...

Happy coaching!
Buswarrior

sledhead · October 05, 2020, 05:17:59 AM

mine was at the auto tran. shifter tower and there was one back in the last bay on the driver side up at the tunnel

dave

blue_goose · October 05, 2020, 07:04:46 AM

Look under the drivers seat. It will have a spring loaded cover. You will need the correct plug to connect.
Jack

mh0pe · October 05, 2020, 05:27:27 PM

Is this it? Looks like a mic jack to me. Nothing in the rear driver side bay except a tach and 24v regulator. Front has an HVAC breaker with a plate on it. I checked around the driver's seat, I didn't find any liftable plates but I did find the jack in the attached picture.

chessie4905 · October 05, 2020, 06:47:21 PM

Yeah, that looks like an intercom mike jack.

blue_goose · October 06, 2020, 05:40:16 AM

On my 1990 102C3 it was on the floor under the right side of the seat. It isn't a round plug, it is about 2 in long and one half in wide. There is also a plug in the last bay on the drivers side of the coach.
Jack

chessie4905 · October 06, 2020, 11:30:07 AM

that 91 or 90? is a ddec, right?

mh0pe · October 07, 2020, 03:23:10 PM

Quote from: chessie4905 on October 06, 2020, 11:30:07 AM
that 91 or 90? is a ddec, right?

91 ddec

mh0pe · October 07, 2020, 05:20:38 PM

Someone said she outright might not have an ECM? I didn't know that's possible on such a recent build.

Busted Knuckle · October 07, 2020, 07:58:17 PM

MCI went as far as 1994 with manual engines, but if ordered a DDEC could have been spec'd as early as '89-90

BK

chessie4905 · October 08, 2020, 06:25:24 AM

Do early ddec have wires under valve covers, in addition to any if it has jakes?

Busted Knuckle · October 08, 2020, 10:51:34 AM

Quote from: mh0pe on October 07, 2020, 05:20:38 PM
Someone said she outright might not have an ECM? I didn't know that's possible on such a recent build.

Post a picture of the top of your engine between the belts.
If it has a DDEC module it will be easy to see in the picture.

BK

Van · October 08, 2020, 11:47:23 AM

Quote from: chessie4905 on October 08, 2020, 06:25:24 AM
Do early ddec have wires under valve covers, in addition to any if it has jakes?

Van · October 08, 2020, 11:59:33 AM

Quote from: mh0pe on October 07, 2020, 05:20:38 PM
Someone said she outright might not have an ECM? I didn't know that's possible on such a recent build.

Look like this?