2005 No Bus issue - need help

[ElecTape]

Just recently pulled dash for heater core replacement. Everything went fine so I thought lol.

After finishing the install and putting it all back together I started the jeep to burp the coolant system. Jeep started fine and ran for several minutes until I shut it off. Let jeep cool down and checked coolant, added some to get to cold line and started jeep. Again, starts fine and let it run while I washed the windows. after I cleaned the windows and sat down in the driver's seat, I noticed the "No Bus" error on the gauges. OK, this has happened to me in my TJ and it was just reseating the gauge plug. so, I pulled the bezel and gauges and reseated the plug. No Joy

In pulling the dash I did disconnect a couple of main electrical connectors on the driver's side. I loosened the 10mm bolts and removed reset and retightened the two that I had messed with. No Joy

Tried....
Disconnected battery Positive overnight. Cleaned battery terminals (very mild corrosion). No Joy
Hard reset for electronics - disconnecting the battery and doing a hard reset (Touching ground and positive terminals together for several minutes). No Joy
Plugged in OBD Scanner to read codes - unable to read codes.
Check both fuse boxes for bad fuses, none found.
Check OBD connector for Bus voltage and power. Pin 4 Ground good, Pin 16 12v good, Pin 6 1.7s volts Pin 14 5.54 volts. Other pins showed 4.72 roughly.
tried reseating the gauge plug again. No Joy
Gauge Cluster reboot - Holding in the trip button on gauges and turning on the key for them to reset. No Joy

After trying gauge reset, jeep starts and dies shortly after starting now.
Checked under hood for any unplugged connectors. None Found.
Checked for ground on engine and grounding straps. All good
Again, messed with resetting the gauges. No Joy, however, the jeep now seems to run as normal.
Tried jiggling harness on gauges. No Joy
Tried to pull codes (Manual method thru gauges) Neither method displayed any codes.

At this point the jeep starts fine and runs but displays "No Bus" and gauges don't function, several Icons lite up.

How do you check for a bad set of gauges?
Could I have left something unplugged in the center consol?

Any help or direction what to look for would be of great help.

 

[ikuo78]

The cluster is probably fine.
There may be a broken BUS circuit.
In the 2003 manual, there seem to be many YL/VT colored wires.
It's a good idea to check around the connector you removed.
Some people may have been able to fix it by removing and reinserting all the fuses to ensure that all the contacts are energized.
I've also heard of people who have fixed it by flashing the ECU.

The BUS circuit connection destinations are listed around the attached page.

You must be registered for see images attach

 

[hotpepper]

Just recently pulled dash for heater core replacement. Everything went fine so I thought lol.

After finishing the install and putting it all back together I started the jeep to burp the coolant system. Jeep started fine and ran for several minutes until I shut it off. Let jeep cool down and checked coolant, added some to get to cold line and started jeep. Again, starts fine and let it run while I washed the windows. after I cleaned the windows and sat down in the driver's seat, I noticed the "No Bus" error on the gauges. OK, this has happened to me in my TJ and it was just reseating the gauge plug. so, I pulled the bezel and gauges and reseated the plug. No Joy

In pulling the dash I did disconnect a couple of main electrical connectors on the driver's side. I loosened the 10mm bolts and removed reset and retightened the two that I had messed with. No Joy

Tried....
Disconnected battery Positive overnight. Cleaned battery terminals (very mild corrosion). No Joy
Hard reset for electronics - disconnecting the battery and doing a hard reset (Touching ground and positive terminals together for several minutes). No Joy
Plugged in OBD Scanner to read codes - unable to read codes.
Check both fuse boxes for bad fuses, none found.
Check OBD connector for Bus voltage and power. Pin 4 Ground good, Pin 16 12v good, Pin 6 1.7s volts Pin 14 5.54 volts. Other pins showed 4.72 roughly.
tried reseating the gauge plug again. No Joy
Gauge Cluster reboot - Holding in the trip button on gauges and turning on the key for them to reset. No Joy

After trying gauge reset, jeep starts and dies shortly after starting now.
Checked under hood for any unplugged connectors. None Found.
Checked for ground on engine and grounding straps. All good
Again, messed with resetting the gauges. No Joy, however, the jeep now seems to run as normal.
Tried jiggling harness on gauges. No Joy
Tried to pull codes (Manual method thru gauges) Neither method displayed any codes.

At this point the jeep starts fine and runs but displays "No Bus" and gauges don't function, several Icons lite up.

How do you check for a bad set of gauges?
Could I have left something unplugged in the center consol?

Any help or direction what to look for would be of great help.

Check your OBD 2 connector under the instrument panel for short or loose wiring

 

[ElecTape]

Figured it out, had a damaged wire in the harness routing thru the dash behind the radio to the gauges and steering wheel. did a repair and all fixed.

Thanx for all the help.

 

[CheddarGau]

If cluster has no bus, find another intact bus that runs off the same circuit. Splice in and you can running overlay to the cluster. If you pulled the dash, you likely broke a wire(s) or left something disconnected. just remember bus wires need to be in a twisted pair to help reduce interference.

You can also re-trace everything you did and find the break. Its also important to make sure its not shorting to anything, since that can cause other modules to go down too.


Edit. Didn't see that he found the fix, but this can also help someone else in the future if they can't find the break.