2006 liberty - no buS - no crank

junkyardjeep · **Joined:** Tue Apr 18, 2023 5:40 pm **Posts:** 12

Went to start my Liberty today and my dash had a no buS message. It will not turn over (no cranking)...Checked the battery and connections and all is good, checked all fuses inside the jeep, all is good. Has anyone experienced this issue and what was the fix.

DieselJeepLuvr · **Posted:** Fri Apr 21, 2023 11:38 am

I'd start by disconnecting your battery terminals, cleaning them, greasing them then reinstalling.
Next do the same for all of your grounds going to the body (there's several).
Next check for any wires that may have rubbed through the insulation or been chewed on by mice.
Have you done the EGR delete? If so check the loose connectors to make sure they are clean, dry and taped shut.

WWDiesel · **Posted:** Fri Apr 21, 2023 1:08 pm

junkyardjeep wrote:

Went to start my Liberty today and my dash had a no buS message. It will not turn over (no cranking)...Checked the battery and connections and all is good, checked all fuses inside the jeep, all is good. Has anyone experienced this issue and what was the fix.

What is the battery voltage reading? Low voltage can cause all kinds of problems! :banghead:

First check ALL fuses on both sides in the TIPM (Power Distribution Center) under the hood with the key in the "ON" position using a 12v test light or volt meter.
Just looking at fuses will not tell you if they are good or not! They must be tested! See picture 1 below.

Since yours is an 06 model, check the wiring harness where it goes behind the fuel filter housing on the firewall. There is a known problem of wiring harness chafing at this location on 06 models.

Check the ground on top of fender cowing behind the left headlight. Take the ground wires lose and clean all the connectors and terminals good and reattach. If rusted out, you may have to replace the wire ends and attach an extension wire from them to a new grounding location or connect them to the negative battery cable end connector. See picture 2 below.
There is also a ground location under the rubber hood cowl gasket right above the master cylinder booster. See picture 2 below.

You got to start with the basics. Have you scanned it for any codes? That may help point you in the direction of the issue. :wink:

Picture 1

Picture 2

junkyardjeep · **Joined:** Tue Apr 18, 2023 5:40 pm **Posts:** 12

I will Start working on the jeep tomorrow morning, - battery was at at 13.1 volts a couple of days ago. No codes on scanner tool. Looks like I have a lot of troubleshooting to do.

junkyardjeep · **Joined:** Tue Apr 18, 2023 5:40 pm **Posts:** 12

Troubleshooting Results. unscrewed and reattached three ground location, firewall, under ABS near PCM and on driver side fender behind headlight. Unplugged the reconnected crankshaft sensor and camshaft sensor. pulled the connectors on the PCM and clamped the battery cables together. Cleaned the battery terminal and cable ends with steel wool before reconnecting the battery. The battery had 13 volts when reinstalled. Turned the key off and on four times looking for any codes, none appeared, thinking I may have lost any codes when I disconnected the battery. Hooked up the scanner tool and no codes found. Ran a ground wire from the battery negative post to the engine. Checked the harness and every wire under the hood. Tested every fuse slot for power and all checked good. I have to find out how to check the relays and the PCM ... Long day......

Summary: no buS - no crank

WWDiesel · **Posted:** Sun Apr 23, 2023 1:59 am

Good update on your tests!
Next things to check/test.
When you turn the ign. switch to the on/run position, does the dash lights come on for their normal test?
1. Try pulling the starter relay and jumpering pins 30 to 87 (9 to 10) with the ign. switch in the on/run position. See diagram below
When you do this 1. test, does the engine start, or does the engine just spin over with the starter and no start?
2. If nothing happens, no starter spin, check to see if you are getting a full 12v at the large starter motor cable connection using a volt meter.
....Next, test to see if you are getting 12v at the starter solenoid control wire (small wire) when you jumper the starter relay. See picture
Report back with results. :POPCORN:

junkyardjeep · **Joined:** Tue Apr 18, 2023 5:40 pm **Posts:** 12

Thanks for the additional options. I stopped by my local junkyard this morning and ask one of the car handlers if he knew anything about " no buS" message on Chrysler products. After telling him the things I had done, he suggested I leave the battery to engine ground in place and add a ground from the engine to the frame. I picked up a couple of cables and made the connections as suggested.

My liberty is alive with no issues I have started it about 15 times since the connections.
thanks again

DieselJeepLuvr · **Posted:** Mon Apr 24, 2023 12:11 am

Nice work! Ground issues can cause all kinds of weird issues.

junkyardjeep · **Joined:** Tue Apr 18, 2023 5:40 pm **Posts:** 12

New no buS issue this morning: Started the day early, I wanted to take care of a couple of errands using the Liberty. The jeep starts but it shuts down within 3 seconds. The dash lights are all lite up and the gauges are not working. The no buS message is displayed. I am feeling some stress related to this and I am going to step away for a couple of days. I hate the thought of having to take my Liberty to a shop,

03black · **Posted:** Mon Apr 24, 2023 12:06 pm

There is a ground on the right side of the engine bay near/under the TCM (Transmission Control Module). I didn't see if you checked that one. Its an easy one to miss.

junkyardjeep · **Joined:** Tue Apr 18, 2023 5:40 pm **Posts:** 12

Back at it today - Unclamped the battery cables from each other - plugged in the PCM -Replaced the ASD relay - double checked all the grounding wires on the motor to frame including the one on the fender near the ABS unit- installed a new OEM crankshaft sensor - checked and cleaned all engine bay sensor connections- checked the battery for voltage (13.1)

Hopped in the seat, turned the key (Fuel pump working) and the jeep started up and ran for about three seconds. no buS message does appear, dash lights comes on and the tach stopped working. Jeep does restart, but the same things happens. I was less confused when it was "no buS - no crank --- Now it cranks - runs for 3 seconds until no buS appears and then it shuts off. I was told earlier today the dash cluster could be the problem, but after looking for an OEM dash, I see it has been discontinued and there is no new old stock around.

I have little faith in dealerships as I have learned that if a code does not show most current service folks do not know where to start. The closest jeep dealership to me does not work on vehicles over 15 yrs old.

Any more suggestions ???

WWDiesel · **Posted:** Tue May 02, 2023 10:40 pm

Based on your description, sounds like you may have a security issue? Is your security light staying illuminated?
Have you tried a different Key Fob?
Item No. 20 on the Instrument Panel Picture below.

From page 16 of the Owners Manual:

Quote:

SENTRY KEY IMMOBILIZER SYSTEM
The Sentry Key Immobilizer System (SKIS) prevents unauthorized operation of the vehicle by disabling the engine. The system will shut the engine down after 2 seconds of running if an invalid key is used to start the vehicle. This system utilizes ignition keys which have an electronic chip (transponder) embedded into them. Only keys that have been programmed to the vehicle can be used to start and operate the vehicle for longer than the 2 second validation time period.
The Sentry Key Immobilizer System does not need to be armed or activated. Operation of the system is automatic regardless of whether or not the vehicle is locked or unlocked. During normal operation, the “Sentry Key/ Security Alarm Indicator Light” (located in the instrument cluster) will come on for 3 seconds immediately after the ignition switch is turned on for a bulb check. Afterwards, if the bulb remains on, this indicates a malfunction in the electronics. If the bulb begins to flash immediately after the ignition switch is turned on, this indicates that an invalid key is being used to start the vehicle. Both of these conditions will result in the engine being shut down after 2 seconds of running. Keep in mind that a key which has not been programmed is also considered an invalid key even if it is cut to fit the ignition for that vehicle.

junkyardjeep · **Joined:** Tue Apr 18, 2023 5:40 pm **Posts:** 12

I am using the keys that has been used for over ten years and the little red light goes out. I can tell if it is going to run longer than 2-3 seconds, the gas gauge will and tach will not work. I think I need to give it up and get the jeep to a shop...

junkyardjeep · **Joined:** Tue Apr 18, 2023 5:40 pm **Posts:** 12

Tried working on the Liberty again today, no positive results still no running jeep. I bounced around the web today and found what I think could be a fix to get the jeep running enough to get it to a dealership. The link has some folks saying it worked for them and some folks say it will cause PCM problems. I am afraid to try because I just put in a rebuilt PCM, dash cluster. I was preparing to try this but after cutting a USB power cable open it has five small wires and the video does not show which wire he connected to the TPS 5v wire. Has anyone tried this and did no damage, if so which wire was used ?

https://www.google.com/search?client=fi ... 6DxjIoskXY

junkyardjeep · **Joined:** Tue Apr 18, 2023 5:40 pm **Posts:** 12

$857.00 dollars - Liberty running - Jeep dealership say they found a short in the passenger seat airbag wiring. They said one of the wires had been rubbing on the seat bottom and the wire coating had worn off and this caused a short. They also replaced a map sensor. I do not think I would have ever found this problem, they said they went through the entire bus circuit before finding the problem.

thank for all the suggestions...

WolverineFW · **Posted:** Mon May 29, 2023 11:25 pm

Keep that shop's number. Apparently they have some actual skilled technicians.

Sent from my SM-S906W using Tapatalk

2006 liberty - no buS - no crank

Who is online