Check Eng. & Stop Eng. Lites

[LarryB]

After a couple of hours of 50-60 mph winding road with use of hi and low jake and manual downshift we were stopped in Traffic. The Check Eng. lite came on steady and the Stop Eng. lite blinked on and off a couple of times. All eng gage readings in the normal range, oil level and coolant levels were checked 'good' prior to the drive. OAT ranged from 89 to 76 degrees.

To turn off the Check Eng. lite I shut down and restarted the engine. Drove without any warning lites for about 30 minutes and while stopped for traffic again, the same occured again.

Any Ideas folks? Thanks!!

[Loc]

Larry,

With a 2000 XL you should be able to get the codes off of the DDEC computer by switching the DDEC read switch (typically located in the area below the drivers seat where the steering gearbox and windshield washer fluid container is located). Then turn the key to on and read the flashes on the stop engine and check engine lights. The Prevost owners manual will have a page for decifering the codes and a recap of how to read them. I would guess it is a low coolant sending unit on the surge tank above the engine on the left hand side.

Loc

[Jon Wehrenberg]

If it turns out the low coolant sensor is the culprit, check the wiring at the terminal, some instances of it being bound to tight with nylon wire ties have created issues. If it turns out to be a bad sensor, a jumper between the terminals on the wire harness will make the codes go away, but you lose the protection so make sure you keep an eye on the coolant.

When you do get stop or check engine lights, always read the codes. If you get a code and you do not have the secret decoder ring, post it and we can interpret what it is saying. For a fee. A large fee. And the answer may even be correct. Or not.

[JIM CHALOUPKA]

Larry, this is the secret decoder ring Jon is talking about.

[LarryB]

OK, I see about the FEE part of this deal later, much later. I'll check the codes and see whats what.

Thanks Guys!

[LarryB]

Loc, I looked for the switch you refer to but have yet to find any switches in that area. I did find some of the DDEC boxes but no switch on any of them.

[Jon Wehrenberg]

Larry,

There should be a way for you to access the codes. Obviously if you can get to a DD shop they can read them, but you should have a way to get them to flash for you on the dash.

The way to read them should be described in the Prevost manual, or if CC has modified the dash there may be a way CC has provided for you to get them to flash.

On my 87 I could put a jumper between terminals A and M on the plug for the reader, and as long as that jumper was there the light would flash and I would get the audible and from either listening to the thing or counting blinks of the light you could determine the code. It has been my experience so far that most codes are sensor problems rather than problems with the engine so they are usually not difficult to repair.

Perhaps someone with your vintage coach can jump in here and tell you how to access your codes. Same thing with your power issue. You need CC specific advice on these.

[truk4u]

Larry,

You can use the check engine light as the source for your code. I don't remember the sequence, engine off, throttle pressed twice or something like that and it will blink the codes. It's in the books and if you don't have it, I'm sure someone here will. I assume you don't have a Pro Driver.

You have a switch in the steering compartment, but it's for blink codes on the ABS.

[LarryB]

Thanks for the help, I'm just going to have to dig deep for the sequence to get the codes, I believe I Did hear 2 beeps as the stop engine lite came on and off so not sure this beeping is related. My DD code pamphlet does not speak of beeps only flashes. The pamphlet describes how to get the codes by "pressing and holding a switch. I'll keep looking.

[Jon Wehrenberg]

I use a reader now, but back in the old days when I jumpered between two terminals I got the flashing light and the beeping. Having an audible, if it does it any more was good because I could jumper the terminals in the steer compartment, hear and count the beeps, and then remove the jumper. I did not have to get back in the coach to see the light flashing.