2018 Ram 1500 electrical problems

[mtm179]

No power to rear passenger windows, rear slider, and sunroof. Rain sensor not functioning as well. Fuses look good and silver circuit breaker replaced. Can anyone point me in right direction before I have to deal with dealership?

 

[HarryS]

Looks like it all comes off the run/accessory relay #1. Pull the relay and check for battery voltage at pin 30, and ground at pin 86 on the relay receptacle. If you have that, then jumper pins 30 and 87 and see if you have function back. If that works, the relay is bad.

 

[SitKneelBend]

Looks like it all comes off the run/accessory relay #1. Pull the relay and check for battery voltage at pin 30, and ground at pin 86 on the relay receptacle. If you have that, then jumper pins 30 and 87 and see if you have function back. If that works, the relay is bad.

You have knowledge, may I ask your source?

 

[HarryS]

Wiring diagrams, and a lifetime of working on electronics.

 

[SitKneelBend]

Wiring diagrams, and a lifetime of working on electronics.

Are they free or do you have a subscription?

 

[HarryS]

My 2013+ Shared Schematics and other OEM Info

Hello all, Since we lost our free TechAuthority Demo access last year I've gathered up some of the schematics and files I had lying around from prior research/mods and helping others and thought I would upload and share with everyone. It's not complete by any means but it's what I've got that...

www.ramforum.com

 

[SitKneelBend]

My 2013+ Shared Schematics and other OEM Info

Hello all, Since we lost our free TechAuthority Demo access last year I've gathered up some of the schematics and files I had lying around from prior research/mods and helping others and thought I would upload and share with everyone. It's not complete by any means but it's what I've got that...

www.ramforum.com

How did I miss this!? Thanks brother!

 

[mtm179]

Thanks for responding. Don’t have means to test relay but replacement is relatively inexpensive. I’ll update result once relay is replaced.

 

[RamDiver]

If you don't already own a digital multimeter, they're an invaluable device for troubleshooting during home repairs and especially automotive adventures.

While this relay has a high probability of being the source of your grief, there are other possibilities as well.

Parts replacement without analysis falls into the parts cannon methodology which is often expensive, not to mention, could potentially be a waste of time and money.

inexpensive digital multimeters

Many of the members here can assist you with troubleshooting and use of a DMM.

,

 

[SitKneelBend]

If you don't already own a digital multimeter, they're an invaluable device for troubleshooting during home repairs and especially automotive adventures.

While this relay has a high probability of being the source of your grief, there are other possibilities as well.

Parts replacement without analysis falls into the parts cannon methodology which is often expensive, not to mention, could potentially be a waste of time and money.

inexpensive digital multimeters

Many of the members here can assist you with troubleshooting and use of a DMM.

,

Completely agree, I bought mine when Radio Shack was going out of business and it has saved me at least $1000 (probably way more, I get it out at least once a month). A man with a multimeter and YouTube can fix nearly all household appliances not to mention all of the automotive applications...

 

[HarryS]

Harbor freight has cheap ones. You can also just swap relays so you don't have to purchase one. But, you really need to test the power coming into the relay, otherwise, replacing it only lets you know the relay state.

 

[mtm179]

Problem not solved after replacing relay. Any suggestions before bringing to dealership?

 

[HarryS]

Again, test for power coming into the relay as I identified earlier.

 

[SitKneelBend]

Problem not solved after replacing relay. Any suggestions before bringing to dealership?

It may seem daunting but what @HarryS is recommending is worth the money upfront. A cheap multimeter could save you hundreds of dollars on a dealer visit and some of things are really simple fixes with the right tool. I'm not gonna lie though, electrical gremlins can be a beast to figure out sometimes too, but you have a decent amount of active participants in this conversation that can help you with where to look.

Going back to your original post. If it's not something as simple as a relay I'd guess bad ground or failing TIPM equally.

 

[mtm179]

I have a multimeter. To test for incoming power, I’m assuming I need to remove relay and test where pins are inserted. Correct?

 

[SitKneelBend]

I have a multimeter. To test for incoming power, I’m assuming I need to remove relay and test where pins are inserted. Correct?

Correct, and the vehicle will likely need to be in run or ACC or Running. I'd start with run (whatever would normally allow those features to have power.

 

[HarryS]

pull the relay, key in on, and look where pin 86 is on the relay, then probe the socket in that location, with the other end of the meter on ground. You should have power, if you do, then test 85 to ground. If that works, then jumper 30 and 87 and see if the windows work. If you don't have power on 85, then you have a problem with the wire from the BCM, or the accessory relay delay control, which is in the BCM, pin 6 of connector c5.

 

[Yardbird]

Look at it this way...The people giving you advice know more about your problem than the dealership techs, and at a price of free,

 

[RamDiver]

I have a multimeter. To test for incoming power, I’m assuming I need to remove relay and test where pins are inserted. Correct?

Just so you have a better idea...




Think of a relay as an electrically actuated switch for a higher current circuit. A low-power switched line, such as a headlight switch, can be used to energize a higher current circuit for halogen headlights. (A headlight circuit is used as an example for simplicity).

With no power, the normally closed (NC) #87A is connected to the common terminal #30.

When the coil across pins 85 & 86 is energized with 12VDC to actuate the relay, the common terminal #30 is switched to the normally open (NO) #87.

Keep in mind that sometimes the engineering is not that straight forward and often pin 85 will be permanently energized with 12VDC (with respect to ground) and another circuit or device will apply a ground to pin 86 to energize the relay. In this instance, with the relay installed in the circuit, you may measure 12VDC on both sides of the coil, this condition will not energize the relay.

Also, keep in mind that often there is no standard as to which side of the coil receives the 12VDC. The relay coil has no polarity, either terminal can be connected to 12VDC or ground.

Hopefully, this explanation provides more clarity than confusion.
Please feel free to ask any questions.

.