Jeep will not start. When I turn the key on after about 30 seconds "no bus" comes up on the odometer. Replaced the ECM with new one from parts store. After replacing, the jeep started and we drove it for about 15 min. Parked over night and next morning it would not start and "no bus" shows up again. I guess something is causing the ecm to go bad. What could this be?
I used to have the NoBUS show up on the odometer also, but always while driving. The immediate fix was a sharp rap on the top of the cluster with my fist. To fix it permanently, I removed the cluster,cleaned the contacts both cluster and harness with spray contact cleaner, then applied some dielectric grease to prevent any further corrosion.
thers only one problem with replacing a computer on a newer model vehicle and that is when you get a computer sometimes you have to "flash" the computer to put in your vin numkber and other things. If you don't your vehicle won't start or it will start and immediately die. The only place I know of that can flash computers in the dealer. A computer for your vehicle is about $900 from the dealer and then you have to pay to have it flashed. Hope this helps.
Running for five minutes sounds like something other than a security system problem (usually shuts off much earlier) but if that has been compromised it needs to be put back together or the trigger wire from the drivers door lock needs to be grounded. I'd look to the throttle position sensor, map sensor, crank position sensor or the ballast resistor on the drivers fender. You need to do tests on those items as all influence the fuel management system after warm up. Test when it is cold and after it shuts off so you don't mistake a part malfunction only when hot. Hands on testing is the ONLY way to determine accurately exactly what is happening there. Anything else is an educated guess!!!
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that is a serious problem on any newer car,
its all electronic and FORT KNOX , tight.
The PCM runs that speedo and odemeter and are now not related
to the insides of the speedo head, like list 100 years. 1900 to now.
POWER TRAIN control MODULE, (old name ECU/ECM)
the PCM stores the miles and then sends them to the Cluster. via the comm bus. (sometimes the BCM is the middle man here) TIPM (Total Integrated Power Module)
the PCM also knows car speed, at all times, (VSS sensor)
and sends live speed data, full time to the head. so scan it.Not doing a scan is FAIL time. a NO WIN deal.
take a scan tool and scan it. see what errors you get.???????
Like VSS dead.? or comm bus errors?, or cluster module errors.?
or? or?
that is first.
also on the newer cars 1998+? there is self test in the FSM.
the FSM is a book , (sold at dealers) and is factory service manual
and in said manual there are the self tests. (for sure)
only how , is a question !!!
on mine.
you push buttons and key actions, then the CLUSTER does its a dance. it wags all gauges. etc.
if the speed dont wag the head is bad.
my 08 jeep, I can do this.
on older years, only the dealer scan tool DRB or? can only do that.
RTM , read the FSM or get it serviced.
there are only 2 choices, on cars now.
1 RTM or 2 get help.
You can not fix modern cars without this manual.
nor with out a scan tool. (I use Innova 3160 to cover jeeps)
alldata.com may have these checks.
costs $15 to look.
alldata, is a on line virtual FSM. and is the best one, lacking the real thing. http://www.youtube.com/watch?v=mEeIuTWjdlg
the below ONLY checks the cluster. !!!
my 08 FSM states: pg 1757 quote
Holding the odometer/trip odometer push button depressed while turning the ignition
switch from the OFF position to the ON position will initiate the CCN self-diagnostic actuator test.
end quote.
now the full page
The instrument cluster actuator test will put the instrument cluster into its self-diagnostic mode. In this mode the
instrument cluster can perform a self-diagnostic test that will confirm that the instrument cluster circuitry, the
gauges and the indicators are capable of operating as designed. During the actuator test the instrument cluster
circuitry will position each of the gauge needles at various calibration points, illuminate each of the segments in
the Vacuum-Fluorescent Display (VFD) units, and turn all of the indicators ON and OFF again.
Successful completion of the actuator test will confirm that the instrument cluster is operational. However, there
may still be a problem with the CAN or LIN data bus, the Powertrain Control Module (PCM), the Totally
Integrated Power Module (TIPM), the Controller Antilock Brake (CAB), the All-Wheel Drive Control Module
(AWDCM), the Occupant Restraint Controller (ORC), the compass module, the Sentry Key REmote Entry
Module (SKREEM) (also known as the Wireless Control Module/WCM), or the inputs to one of these
electronic control modules. Use a diagnostic scan tool to diagnose these components. Refer to the appropriate
diagnostic information.
1. Begin the test with the ignition switch in the OFF position.
2. Depress the odometer/trip odometer switch button.
3. While still holding the odometer/trip odometer switch button depressed, turn the ignition switch to the
ON position, but do not start the engine.
4. Release the odometer/trip odometer switch button.
5. The instrument cluster will simultaneously begin to illuminate all of the operational segments in the VFD
units, and perform a bulb check of each operational LED indicator. The VFD segments and LED
indicators remain illuminated as each gauge needle is swept to several calibration points and back. If a
VFD segment or an LED indicator fails to illuminate, or if a gauge needle fails to sweep through the
calibration points and back during this test, the instrument cluster must be replaced.
6. The actuator test is now completed. The instrument cluster will automatically exit the self-diagnostic
mode and return to normal operation at the completion of the test. The actuator test will be aborted if the
ignition switch is turned to the OFF position, or if an electronic vehicle speed message indicating that the
vehicle is moving is received over the CAN data bus during the test.
7. Go back to step 1 to repeat the test, if necessary.
Hey Sidney. On G6 it has a pass lock anti theft- in which your key is programmed into the computer. If the key is not programmed into the computer or ECM, then nothing at all, heres the steps, and where it says a new cut key on 1, ignore that, just use your key, and also you will need to take your g6 into the dealership and have them reflash the ECM, and program the VIN number into your new ECM, if not it might throw the check engine light.
1. Insert a new cut key in ignition and turn key to the ON position for
10 minutes and 30 seconds.
2. Within 45 seconds turn the key to OFF and then back to the ON position for
10 minutes and 30 seconds.
3. Within 45 seconds turn the key to OFF and then back to the ON position for
10 minutes and 30 seconds.
4. Turn key OFF then back ON. The key is now programmed.
Start vehicle to test key.
Hi, the no BUS is usually a seriuos issue with engine controller communication. Can you check and see what trouble code is stored in the PCM (engine comuter)? This code needs to be retrieved with a code reader available at most auto stores for around $40. If you can give me the code, I can tell you exactly what is wrong and what will be needed to repair your Jeep.
Your ecm is going bad. If you haven't noticed yet, the vehicle will only start once the check engine light comes on, on the dash. That's the ecm finally sending power to the relays that feed the fuel pump and ignition systems. If you're mechanically and electrically handy you can remove the ecm, disassemble it and replace the three power capacitors inside. If not, just have the ecm checked and replaced.
"no bus" means the communication line (wire) between the modules is down. It could be shorted to ground or power externally or a module itself is pulling it down. The engine, transmission, antilock brake, airbag, instrument cluster, and overhead console modules all use the same bus line to relay information to each other. One way to isolate the faulty module is to disconnect each module one by one with the key on until the "no bus" goes away and the odometer comes back to normal. This isn't an easy fault to find since the PCI bus line runs everywhere but I would start with isolating modules. I hope this helps.
All the modules are connected together to communicate with each other via the PCI bus. It is possible that one of the modules is pulling the bus down.Since the vehicle won't start it could be any one of the modules. It will be a process of elimination to find the faulty one by disconnecting them one at a time. Here are a few, powertrain control module (the one you replaced) Instrument cluster, overhead console, anti-lock brakes, airbag. Since the cluster unplugged wont read anymore, just try to start the vehicle to see if that was the one. Otherwise see if the odometer message of "no bus" goes away after each one is unplugged.
From the official Durango shop manual......(abbreviated)
Self Diagnosis Test
Vehicle key position is OFF ,or able to pull key out.
Hold in the trip odometer button (dont release yet)
Turn key to the ON position (one notch), but DON'T try to start the engine
Continue holding the trip button for about 10-12 seconds until CHEC appears in the odometer display
Release the trip button.
Series of three digit numeric failure codes may appear.
If no failure message appears, the self diagnostic test will proceed as described in step 6
900-CCD data bus not operational, check CCD data bus connections at cluster, check the cluster fuses,check the CCD data bus bias, cehck the CCD data bus voltage, check the CCD data bus terminations.
920-cluster is not recieving a vehicle speed message from the PCM, check PCM software level and reflash if required, use the ($2500+) DRBIII scan tool to verify the vehicle speed message is being sent by the PCM
921-the cluster is not recieveing a distance pulse message from PCM,check PCM software level and reflash if required, use the ($2500+) DRBIII scan tool to verify the distance pulse message is being sent by the PCM
940-the cluster is not recieving an airbag lamp-on message from the ACM, check the CCD data bus connections at the ACM, check the ACM fuse.
950-cluster not recieving an ABS lamp-on message from the CAB, check CCD data bus connections at the ACM, check the ACM fuse.
960- clsuter not recieving a PRND21 message from the TCM, check the CCD data bus connections at the TCM, check the TCM fuse.
999-An error has been discovered, record the failure message, depress the trip odometer reset button to continue the Self-Diagnostic Test
Step 6
Instrument cluster will test each segment of the odometer (all first, then each one seperately)
Step 7
Bulb test
Step 8
Gauge test
Step 9
test completed
The instrument cluster will return to normal operation at the completion of test, if ignition switch turned off, or a vehicle speed message indicating movement recieved from the PCM on the CCD data bus.
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