Radio does not work after ignition [Archive] - The Chrysler Minivan Fan Club Forums

: Radio does not work after ignition

02-15-2010, 03:22 AM
I have a 2004 T&C Minivan with only 35K miles. I recently changed the battery (after 6 yrs). Its been a couple weeks since the change and today the Radio, which has a navigation did the following:

When I insert the key and turn it to the position so that the accessories work, everything works fine. The minute I turn the key to ignition and start the engine, The radio switches off. Everything else, works fine. Another intereting thing is that, if the radio was set to CD changer, I would still hear the CD from the CD changer playing as that would still be on after ignition. Also, I can control the volume of the CD changer from the radio that "has no power" after ignition. I cannot however change the mode from CD changer, to AM/FM or NAV after ignition as none of these buttons work. There is no power on the head unit and not even the time is displayed.

My guess is that there is nothing wrong with the head unit as it works fine when power is supplied to it prior to ignition. I am sure that power is being supplied from a different source after ignition takes place.

Can anybody advise as to what the problem might be. This is not covered under the 7yr/70000ml drivetrain warranty. Please help.

02-15-2010, 08:23 AM
First things first, pull the IOD fuse for about 15 minutes. Post back and let us know if that helped!

02-15-2010, 11:19 AM
First things first, pull the IOD fuse for about 15 minutes. Post back and let us know if that helped!

I was going to say the same thing. Seems to cure a lot of problems.
Hope it works.

02-15-2010, 01:19 PM
I pulled the IOD fuse out as you suggested this morning. It did not resolve the problem.

02-15-2010, 01:28 PM
Sounds like a possible head unit problem. The fact that the head unit is required to take the signal from the CD changed and send the sound to the speakers shows that it is still on, somewhat.

02-15-2010, 01:35 PM
Any more clues??? Since the battery was changed a while ago, that can be ruled out. what changed right before this... service at a dealer? hit a hard bump in the road?, went through a large rain storm/puddles. Has the radio bezel been off to fix a heat control problem?

Sounds like a relay is not working or the PCM is not doing its job right? How are the connections at the battery and the RB1 radio? Have you checked the fuses?

Have you tried taking the NAV DVD out and trying it? this brings up another question now.. did you upgrade the NAV DVD? although if it works with the engine off.. I guess this is ruled out.

If I understand it correctly... the volume knob and other features (balance/fade) are sending signals over the pci bus to tell the amp to raise and lower the volume. Hope I am not confusing this with the Pacifica I once owned.

02-15-2010, 03:17 PM
It did rain pretty heavy out here in L.A. the last couple weeks, but I did not have the prblem during that period. As for hitting hard bumps...the answer is no. The replacement battery is an Exide 34-60 model.

I tried removing the fuse and the Accessory relay for 15 min again. The problem did not get resolved. After switching the engine off, the only way I can get power to the head unit, is to remove the key, open then shut the driver side door, wait a couple of minutes. Insert the key to the pre-ignition position....and magically power gets restored to the head unit and everthing works.

I read the thread about a similar problem like mine , but the front and rear blowers and elec tric windows do not work. I do not have problems with those accessories.

Also, while I had power retsored to the head unit, I remove the Nav DVD...there were no scratches, blemishes etc. This is probably the first tiome I removed the CD since I put the free replacement disk in the 4 years ago. The Nav rest itself....there were no issues.

Note: when power is lost to the head unit after ignition, the only thing that works is the power/vol knob. I can use this to control the CD changer only if the head unit was in CD changer moder before the powere was lost. None of the other buttons work. On the RB1 radio the LCD screen is blank. I cannot access even tone, fader or balance functions.

I hope this helps...this problem is driving me nuts after 6 years of trouble free motoring....Thinking about taking it to the dealer

02-15-2010, 03:43 PM
Maybe you can determine if something else does not work to help pin point it? All climate controls work? You said all the locks work OK after the car is on so we can skip that one. How about the power outlets front and rear. Trying to see if there are other things that don't work, then we can rule out the radio for sure. Any park sensor or heated seats? Basically try any accessory I guess.

02-15-2010, 04:11 PM
Also.. with the car on have you tried cycling the power radio knob? When it does work, it the key in on position or accessory? Does it work in both modes?

02-15-2010, 04:34 PM
All other accessories work....confirmed in both modes of the (Pre-ignition & post ignition)
The powere knob also works in both modes.

New symptom... I had to run a quick errand - drop off a movie. Just got into the van and drove off. Everything worked fine. I dropped off the movie... got back in started the van...everything continues to work. I get get back home thinking that we're good and the problem is solved. So i switch off the van then try it again ...and the problem recurs. Now I dont trust it becuase the problem seems to be intermittent...whats up with that!

02-15-2010, 10:58 PM
The power that comes back from the switch sounds like the key. If you can follow it back to whatever relay sends power to the radio, it sounds to me like that is where it is faulty or corroded. It comes back and goes to the radio from the accessory mode, in the start position, it is not getting power. I don't have the schematics, but I would follow the power from the "on" connection to the radio. Any connection that the accessory and ON line do not have in common.

02-17-2010, 10:46 AM
Thank you all for your advice. Heres what has happended so far.

Took the van to the dealer. They basically said that all they would do is replace the head unit $500. I disagreed that that was the problem. The service advisor suggested that I take the vehicle to a local auto audio electronics store which deals in this kind of stuff.

Heres the thing though. After demostrating the problem to the Service advisor, I found that I can get around this by just turning the key quickly from the off position to ignition, when starting the vehicle. When I do this I get full functionality of head unit after the vehicle has started. Who knew? Anyway, for now I am going to monitor this. If I get a fix for this issue, I will post this up here again.

Thank all once again. I really appreciated your support. This was the first time I joined a forum for a car problem and my expectations were surpassed!!!!

02-19-2010, 09:49 PM
Ignition switch. That is my final answer, lock it in.