Two Cadillacs, Two Problems

1996 Cadillac STS and a 1997 Cadillac Catera

Dec 14, 2006 Vincent Ciulla

We have two Cadillacs this time. One with an "EXP 100" Message code and another with no defrosters.

Question: Cadillac STS "EXP 100" Message

I have a 1996 Cadillac STS with 128,000 km (77,000 miles). I'm getting a message "Service Transmission" "EXP 100". It started about a month ago and would come on for a few seconds every week or so but now it comes on and stays on almost all the time. The manual says this message is displayed when the computer detects a problem with the transaxle. But the car seems to be running fine, although putting the car into gear does seem a bit jerky now.

What should I do? What type of service does a transmission require other than replacing the entire transmission? My mechanic checked the fluid level and quality a month ago and all is fine. Any advice? Can you direct me to any web sites to read more about this?

Regards,

Paul

Answer:

Basically that message is telling you it's time to service the automatic transaxle. To reset the message:

  1. Key "On" Engine "OFF".
  2. Press and hold OFF & REAR DEFOG buttons (between 5 & 20 seconds) on the Climate Control simultaneously until the Trans Fluid or Life Reset message appears.

This transmission requires a transmission filter and fluid change. I would advise against a transmission flush since that can often do more harm than good.

Question: Cadillac With No Defrost

I have a 1997 Cadillac Catera and I turn the defroster on and it doesn't defrost. I hear the sound and see the lights and everything on the control panel but the air doesn't come out. I hear it but I don't see it. Another thing is the light on the A/C control panel is bright, but when I turn my lights on it gets dim. That is a new thing. It was working fine just the other day but now it doesn't heat up my car or defrost.

I don't know if its connected to my front lights because when I turn them on the defrost lights go dim. Or if it's the blower fuse. So here is the final scenario. The A/C /heater control lights up and I hear the sound of the heat but I don't feel the heat anywhere so if you know what the problem could be please e-mail back immediately.

Thank you sooooo much,

From someone who doesn't know much about the cars I drive.

Answer:

Does air come out of any of the vents, or is it just not coming out of the defroster vents? If there is no air coming from any of the vents then you have something blocking the air intake. I found that it is common to find paper napkins that fell out of the glove box blocking the blower motor.

If it is just the defroster vents then you will need to take it to your Cadillac Dealer. He needs to connect his scanner to the HVAC system and pull the Diagnostic Trouble Codes (DTC's) for the HVAC system to pinpoint what's wrong.

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