High beams - CTM or mutifunction switch
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High beams - CTM or mutifunction switch
Sorry if the repost is a hassle for the admins; I originally posted this in the wrong subforum!
Not a gearhound, but I'm trying here. I've got a weird problem with the high beams on our '01 Dakota, 3.9L V6 with 106K miles. Based on reading here and elsewhere, I think I've got it nailed down. Here's what we're seeing. If you turn on the headlights, low beams come on ok. If you flick on the high beams, they go dark. If you turn off the headlights, then turn them back on, the high beams come on. If you then flick over to low beams, then back to high beams, the headlights shut off. Even when the high beams aren't working, you can get them on by pulling the turn signal stalk back all the way. The low beams work fine throughout this.
While I see some folks saying that the multi function switch in the turn signal stalk was the culprit, this seems to me to be most likely a problem in the Body Control Module, which from what I'm reading is also called the Central Timing Module or Time & Alarm Module. Three questions:
1. Does this solution make sense to folks who know more than me (most of you!)?
2. Do I need to worry about any programming on the BCM/ CTM / T&A to work with my VIN? I'm thinking that the remote door fob unlock wouldn't work with the new module, but that we could get a locksmith to either reprogram the clicker or set a new one to work with the new BCM; does that make sense? Is there any other programming to worry about if it's a direct part# replacement?
3. We previously had to replace the ECM, due to a "No Bus" error. Given that we had the failed ECM, and now this module, should we be digging deeper into electrical issues?
One additional note that I don't think is related, but it's a similar kind of weird issue. The cruise control comes on ok, and the speed sets alright. But if you brake or turn off the cruise, it shuts off and won't come back on until you turn off the engine and restart.
THANK YOU!
Not a gearhound, but I'm trying here. I've got a weird problem with the high beams on our '01 Dakota, 3.9L V6 with 106K miles. Based on reading here and elsewhere, I think I've got it nailed down. Here's what we're seeing. If you turn on the headlights, low beams come on ok. If you flick on the high beams, they go dark. If you turn off the headlights, then turn them back on, the high beams come on. If you then flick over to low beams, then back to high beams, the headlights shut off. Even when the high beams aren't working, you can get them on by pulling the turn signal stalk back all the way. The low beams work fine throughout this.
While I see some folks saying that the multi function switch in the turn signal stalk was the culprit, this seems to me to be most likely a problem in the Body Control Module, which from what I'm reading is also called the Central Timing Module or Time & Alarm Module. Three questions:
1. Does this solution make sense to folks who know more than me (most of you!)?
2. Do I need to worry about any programming on the BCM/ CTM / T&A to work with my VIN? I'm thinking that the remote door fob unlock wouldn't work with the new module, but that we could get a locksmith to either reprogram the clicker or set a new one to work with the new BCM; does that make sense? Is there any other programming to worry about if it's a direct part# replacement?
3. We previously had to replace the ECM, due to a "No Bus" error. Given that we had the failed ECM, and now this module, should we be digging deeper into electrical issues?
One additional note that I don't think is related, but it's a similar kind of weird issue. The cruise control comes on ok, and the speed sets alright. But if you brake or turn off the cruise, it shuts off and won't come back on until you turn off the engine and restart.
THANK YOU!
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From: MA
It does sound like the CTM is the likely culprit for your headlights. I'd check the ground for the headlight switch though first. The CTM and the headlight switch both use a common ground, G208. If you follow connector 1 down from the CTM you'll find it.
The switch provides a "sense" signal, basically a ground to the CTM, to turn on the headlights.
Bad grounds can cause all sorts of strange issues.
You may have issues with the programming. Yes, the RKE won't work. You must make sure you get the same options, especially the alarm (VTSS) and if you have SKIM (security key) it will need reprogramming too.
The speed control is through the PCM so, likely a different issue. Yes, they can all be related. All the modules are on the same PCI bus however.
If you can find someone with a DRBIII or equivalent they should be able to help diagnose these issues.
The switch provides a "sense" signal, basically a ground to the CTM, to turn on the headlights.
Bad grounds can cause all sorts of strange issues.
You may have issues with the programming. Yes, the RKE won't work. You must make sure you get the same options, especially the alarm (VTSS) and if you have SKIM (security key) it will need reprogramming too.
The speed control is through the PCM so, likely a different issue. Yes, they can all be related. All the modules are on the same PCI bus however.
If you can find someone with a DRBIII or equivalent they should be able to help diagnose these issues.