99 Remote Radio Buttons & Cruise Control - Function Problems

[Joe Mc]

In advance, sorry for long post, thanks for reading and I hope someone can help (truck in my signature), here goes:
Remote Radio Buttons:
For several years (probably more like 5-7) when I'd push the volume down button (right side bottom) the channel would change. Volume up button has always worked as designed.
When I push the channel scan down button (left side bottom) the volume goes up. Channel preset (left side middle) and channel scan up (left side top) have always worked as designed.
Cruise Control:
Also several years, "sometimes" when I'd hit cruise off/on button (left top) the cruise light wouldn't come on and no cruise, sometimes if I hit it 2 times it would work. Most often the cruise on worked as designed. There have been occasions where no matter what I did the cruise would not come on, meaning; change tilt on the wheel, turn the wheel = no work. I'd pull over, turn ignition off, restart and it would work as designed????

Yesterday I decided to investigate. Removed air bag, knee bolster panel and other plastic covers at steering column to dash. Removed the radio and cruise buttons and followed ohms, continuity and ground check test procedures as outlined in my trusty Dodge Shop Manual. All tests came back "OK". So I inspected all wiring harnesses for small insulation nicks that might be causing a ground out/short circuit situation at; the steering wheel harness, then from that harnesses connector (disconnected) thru the clock spring (BTW: only 3-4 years old and didn't fix problem back then), then disconnected the plugs from column into clock spring to the CTM (whatever box that controls all this stuff under dash) then disconnected the plugs into the CTM. All wires to CTM read good. I decided to check continuity wire to wire for each harness, plug to plug, wire for wire, all read fine = nothing open. Tested the radio switches for correct ohms (per shop manual) and they read as listed.

I then looked at the back of the radio switches and pushed on the buttons noticing where contacts were made based on button pushed. Interesting, two little copper tabs that when you push a button another copper tab moved to make contact with the other two. I noticed the "other" copper tab seemed to be a bit dirty. I took a scribe tool and lightly scraped the surface that would connect with the two tabs, then used some electrical connector cleaner (CRC) giving a little shot in each areas and then followed with blowing out with air. I put everything back together, managing not to deploy the airbag - LOL, and went for a drive. Miraculously everything worked perfectly! Channel up and down buttons worked, the volume up down worked and not once did they act as before. Also, did same cleaning on the cruise on/off and increase/decrease speed/coast (cancel) buttons. I was so pleased that everything was once again working as when I first purchased it back in 01.

Yep, you guessed it, this morning I went for a ride no matter what I did the cruise wouldn't come on - I turned off the truck & restarted it, moved the tilt on the wheel up down several times turned the wheel right and left - no cruise! WTF!!! Oh, the radio buttons... channel down increased volume and volume down changed the channel, but when I moved the tilt they seemed to work as designed.

Outside of purchasing all new buttons (radio & cruise), harnesses and CTM, I'm at a loss? Help!?!

Oh, and this just started a few months ago; I go for coffee in the morning and let the truck run while I'm inside (locked of course) and when I get back in and place the tilt back to where I like it I've noticed (only a few times) that the Brake, Check Gages and ABS lights on the dash light and then go out? Almost like when you start the truck up there's that short time when dash lights stay on and then automatically go out... I'm wondering if the 216,000 mile ignition switch might be the culprit? I've checked (and not by just looking at) all chassis grounds, new high tech battery end terminals (both batteries) and the ground on engine to battery and frame connections are clean and tight.

I'm about to loose my mind here, #@$%!:{

Thanks gang!

 

[Joe Mc]

Update: Yesterday I went to visit a buddy of mine at his shop and the cruise, radio buttons worked fine. Then on the way home, a few hours later, couldn't get cruise to come on, tried shutting down several times, pushing button multiple times, moving steering column tilt - nothing. Today after pushing cruise on/off button 6-7 times it worked fine. I could even turn it off of cruise and with one regular push of the button turn it back on. Radio buttons worked fine too. #@$%!

 

[Road Dog]

The wiring for the radio buttons on the steering wheel don't go to the radio. They go to the PCM (I think) and the PCM sends commands over the CCD (data bus) to the radio. I would expect the cruise control and radio buttons go through the same wire harness and connector(s) to the PCM. Maybe a connector under the dash or engine compartment is loose or dirty.

 

[Joe Mc]

Road Dog, thanks for reply. You are 100% correct "wiring for the radio remote buttons don't go to the radio". they go from the buttons on the wheel thru the clock-spring (only a few years old) to the "radio control MUX" connection on the CTM (Central Timer Module) and somehow thereafter the radio receives signals???

Trying to keep this post alive so I don't just start thinking of throwing new switches in the steering wheel to no avail.

NOTE: Cruise worked flawlessly (yes cruise switches wiring is all part of the radio button wiring under the horn/airbag) this AM. I stopped and shutdown for 5 - 10 minutes to get coffee and then it wouldn't come on. As I was sitting at a light I placed the tilt wheel down, held it from going up as I held back the tilt lock lever and then let it go up by itself. This wasn't a big spring up by any means, in fact to get the wheel in the full up position you have to help that old weak spring, but as I moved it to the top and then back down to where I usually keep it when driving, the chime sounded and the idiot lights on the gage cluster lit up just like when you start the engine for about 5-10 seconds. Once again a question asked in this post "is it possible the ignition/key switch is going south"? Another thought, but I'm almost certain not, is there wiring that moves with the tilt up/down on the top of the steering column (swivel area)?

 

[KATOOM]

I'm just curious as to how you removed the buttons. I may need to.....

 

[Joe Mc]

Kat, Tha KS for your reply. I highly recommend that you do as did I when I first acquired my truck in May of 01 with 75k miles, note it now has 217. Go to Genosgarage.com and for about $100 buy the Dodge Shop Manual, recommend the paper version as you can place book marks in those areas you want to remember for easy finding later on.
Above being said, another recommendation is to join TDR, I see you are a trial member, just do it and join, the $35/year cost is returned at least tenfold in information and discounts as well as an awesome quarterly magazine and ability to place ads in the site classifieds.

To your question, and all of this in more detail is for sure in the previously mentioned shop manual; disconnect both negative battery terminals and wait about 5 mins so the airbags disperse electric charges, we don't want to deploy the airbag on the steering wheel right? On the back side of the steering wheel in small pockets locate 2 he cap screws, I believe they're 8mm, remove them. Slowly remove airbag/horn assy and disconnect wiring, tip the yellow connection on the center of the airbag will be really snug and you might want to, gently and working a few areas as you go around the connector, use a flat pry tool/screwdriver to loosen it. Set the bag/horn assy aside and you'll see the screws to remove the cruise function buttons, 2 each and I believe they are torx, once the cruise buttons are out of the way you'll notice the radio buttons are snap fit into the plastic backside of the steering wheel. Look at these snap fit area closely and you'll see which side to lightly depress so you can feed the buttons out, the back side, of the wheel. BTW, the shop manual gives instructions on how to test the buttons with an ohm meter to see if they have the correct resistance for each function.

 

[KATOOM]

Thanks Joe. I appreciate the information.

 

[Joe Mc]

OK so it's been a few weeks since I updated. Same old same old thing is, and at times - isn't, happening. An interesting thing is; when I start up and head down the road and select cruise, if the dash "cruise" light will not come on, I place trans in "N", turn key off and start back up, place trans in "D", select cruise, then it works fine. I keep thinking something in the ignition switch or wiring to and from? Although, I had all connections off (from "everything") at the steering wheel to column and column to other devices under dash, cleaned them all, checked for continuity (batteries disconnected) and visually inspected every inch of wires for a knick or otherwise compromise and it's all good.

Thoughts, ideas, previous experiences all appreciated.

 

[KATOOM]

Has anyone suggest possibly the Central Timer Module (CTM) isnt functioning right? I believe its in control of all radio functions and lots of other accessories as well.

 

[Road Dog]

I vaguely remember that a noisy alternator interferes with the transmission (TC lock/unlock) and, in turn, interfere with the cruise control.

The clock spring is a long flat ribbon cable and cracks in the wires will interfere with the signals (which are typically 5V) and pass any visual inspection. The outer insulation is fine; it's that wires that are broken.

 

[KATOOM]

Yes, excessive AC voltage is bad news for neighboring sensitive electronics like the APPS, VP, and transmission sensors. Its very easy to test and alternator for excessive AC voltage too. Youtube has some videos to help if someone's not sure how.

 

[Joe Mc]

Thanks. I do have DTT noise filter which has been in place since 2002 because there was the OD in/out issue at 40-45mph. The clock spring was replaced probably 3 or 4 years back due to issues with steering wheel buttons only working when the wheel was at other than "center" as in driving down the road. I've inspected all wires from the wheel thru the column and to the devices the wires feed to IE: CTM, etc. all are free of insulation compromises.

 

[crabman]

Try rebooting the ECM by disconnecting the batteries for 1/2 hour.

 

[Joe Mc]

That's been done when recently checking all connections mentioned above. At this point I'm leaning towards a bad CTM. Interestingly when I start the truck up and while all the dash lights are still lit if I press cruise button it stays lit and works. When I stop for a while, like at the ATM, I notice when I'm done the light for cruise is out. If I press to turn on it will not go on, shut down, start up, hit cruise it works fine. More to come.

 

[LorenStrodtman]

Hello, Joe
I am having problems with the cruise on my 01 as well and found this thread in a search on the subject. In my case the cruise light comes on, but it won't set. I, too, have changed the clock spring since they are a known problem, and I've ensured the vacuum system is good. Have you resolved the issue with your cruise, and if so, what was the diagnosis?

 

[Joe Mc]

Probably around 03 or 04 I had same thing with cruise = light would come on but would not set. I ended up replacing the cruise servo (I think that’s what it was called?) located below the left (dr. Side) battery and that solved the problem. I think it was about $70, but could be off as it was around 14 yrs ago. Since then I’ve totally forgotten about the cruise and radio controls as something else is going on that I haven’t figured out yet? I’ve replaced the clock spring recently and all would work fine = when sitting in drive way, then as soon as I put in gear and headed down the road - nothing. I’m thinking the CTM (Central Timer Module) or something else electronically is wrong. If I ever figure out what it is I’ll post up here. BTW it seems the cruise light will come on and work if I hit the cruise button before all the dash lights go out upon start up, but this only works sometimes???? Definitely something electronic ....