Hello,.. I have a 2001 dodge ram 1500 5.9L 4X4. The cluster is dead, it has gone dead a few times before and came back on it's own. The cluster reads "NO BUS". All the fuses under the hood and inside are good. The truck still starts and runs good. I've checked all wiring for bad grounds, and fuses none are bad. If the PCM is bad would it still start and run?...
this is going to require looking at the wiring diagrams...let me see if i can find a set...can you rock the key from the ON position to the off and back on... ON, off ON, Off ON. OFF on off ON.. with the final position in the ON position within 10 seconds and see if the odometer changes from miles driven to various codes...or do you have a scan tool????there are also tests for the cluster by its self..
Symptom:*BUS +/- SIGNALS OPEN OR NO RESPONSE FROM INSTRUMENT CLUSTERPOSSIBLE CAUSESATTEMPT TO COMMUNICATE WITH ANOTHER MODULEOPEN GROUND CIRCUIT(S)OPEN FUSED IGNITION SWITCH OUTPUT CIRCUITSOPEN FUSED B+ CIRCUIT(S)OPEN PCI BUS CIRCUITINSTRUMENT CLUSTERTEST ACTION APPLICABILITY1 Turn the ignition on.With the DRB, attempt to communicate with the Airbag Control Module (ACM).With the DRB, attempt to communicate with the Controller Antilock Brake (CAB)module.Was the DRB able to I/D or communicate with any of the modules?AllYes ! Go To 2No ! Refer to symptom list for problems related to the PCI BusCommunication Failure.Perform BODY VERIFICATION TEST - VER 1.2 Turn the ignition off.Turn all lights off.Disconnect the Instrument Cluster harness connectors.Using a 12-volt test light connected to 12-volts, probe each ground circuit.Is the test light illuminated for each circuit?AllYes ! Go To 3No ! Repair the ground circuit(s) for an open.Perform BODY VERIFICATION TEST - VER 1.3 Turn the ignition off.Disconnect the Instrument Cluster harness connectors.Turn the ignition on.Using a 12-volt test light connected to ground, probe both Fused Ignition SwitchOutput circuits.Is the test light illuminated for both circuits?AllYes ! Go To 4No ! Repair the Fused Ignition Switch Output circuit for an open orshort. Refer to the wiring diagrams in the service information.4 Turn the ignition off.Disconnect the Instrument Cluster harness connectors.Using a 12-volt test light connected to ground, probe each Fused B+ circuit.Is the test light illuminated for each circuit?AllYes ! Go To 5No ! Repair the Fused B+ circuit for an open or short. Refer to thewiring diagrams in the service information.Perform BODY VERIFICATION TEST - VER 1.5 Note: Ensure there is PCI Bus communication with other modules on thevehicle before proceeding. If not, refer to the symptom list from the menuand repair as necessary.Disconnect the Instrument Cluster harness connectors.Use Scope input cable CH7058, Cable to Probe adapter CH7062, and the red andblack test probes.Connect the scope input cable to the channel one connector on the DRB. Attach thered and black leads and the cable to probe adapter to the scope input cable.With the DRBIIIt select Pep Module Tools.Select lab scope.Select Live Data.Select 12 volt square wave.Press F2 for Scope.Press F2 and use the down arrow to set voltage range to 20 volts. Set Probe to x10.Press F2 again when complete.Connect the Black lead to the chassis ground. Connect the Red lead to the PCI Buscircuit in the Instrument Cluster connector.Turn the ignition on.Observe the voltage display on the DRB Lab Scope.Does the voltage pulse from 0 to approximately 7.5 volts?AllYes ! Replace the Instrument Cluster in accordance with the serviceinformation.Perform BODY VERIFICATION TEST - VER 1.No ! Repair the PCI Bus circuit for an open.Perform BODY VERIFICATION TEST - VER 1.196COMMUNICATION*BUS +/- SIGNALS OPEN OR NO RESPONSE FROM INSTRUMENT CLUSTER— Continuedsay... Please invest if you have a harbor freight tools near you in one of their computer safe circuit testers.. Cen-Tech 98709 Computer Safe Automotive Logic Probe Computer Safe Automotive Logic Probe Item #98709
one warning the info above is for a 2002 ram..there is a bunch more info.. see what you can diagnose with the above..your cluster could also be bad..but please DIAGNOSE FIRST..
this is the section i was looking for..ACTUATOR TESTWARNING: ON VEHICLES EQUIPPED WITH AIRBAGS,DISABLE THE AIRBAG SYSTEM BEFOREATTEMPTING ANY STEERING WHEEL, STEERINGCOLUMN, OR INSTRUMENT PANEL COMPONENTDIAGNOSIS OR SERVICE. DISCONNECT AND ISOLATETHE BATTERY NEGATIVE (GROUND) CABLE,THEN WAIT TWO MINUTES FOR THE AIRBAG SYSTEMCAPACITOR TO DISCHARGE BEFORE PERFORMINGFURTHER DIAGNOSIS OR SERVICE. THISIS THE ONLY SURE WAY TO DISABLE THE AIRBAGSYSTEM. FAILURE TO TAKE THE PROPER PRECAUTIONSCOULD RESULT IN ACCIDENTAL AIRBAGDEPLOYMENT AND POSSIBLE PERSONALINJURY.The instrument cluster actuator test will put theinstrument cluster into its self-diagnostic mode. Inthis mode the instrument cluster can perform a selfdiagnostictest that will confirm that the instrumentcluster circuitry, the gauges, and the indicators arecapable of operating as designed. During the actuatortest the instrument cluster circuitry will positioneach of the gauge needles at various calibrationpoints, illuminate all of the segments in the VacuumFluorescent Display (VFD) units, turn all of the indicatorson and off again, display any Diagnostic TroubleCode (DTC) information, and display the numberof ignition key cycles that have occurred since theDTC was detected. It is suggested that a note padand pencil be used to write down any fault informationthat is displayed during the test for reference.Successful completion of the actuator test will confirmthat the instrument cluster is operational. However,there may still be a problem with the PCI databus, the Powertrain Control Module (PCM), theFront Control Module (FCM), the Transmission ControlModule (TCM), the Transfer Case Control Module(TCCM), the Airbag Control Module (ACM), theController Anti-lock Brake (CAB), or the inputs toone of these electronic control modules. Use aDRBIIIt scan tool to diagnose these components.Refer to the appropriate diagnostic information.(1) Begin the test with the ignition switch in theOff position.(2) Depress the odometer/trip odometer switch button.(3) While still holding the odometer/trip odometerswitch button depressed, turn the ignition switch tothe On position, but do not start the engine.(4) Release the odometer/trip odometer switch button.(5) The instrument cluster will simultaneouslyilluminate all of the operational segments in bothVFD units, perform a bulb check of each operationalLED indicator. The VFD segments and LED indicatorsremain illuminated as each gauge needle isswept to several calibration points and back. If aVFD segment or an LED indicator fails to illuminate,or if a gauge needle fails to sweep through the calibrationpoints and back during this test, the instrumentcluster must be replaced. Following these tests,the actuator test will proceed as described in Step 6.(6) The text “C Code” is displayed in the odometerVFD for about three seconds. If there is no storedfault information, the display will show two pairs ofzeroes in the format “00” “00”, which indicate thatthe display of fault information is done. If there isstored fault information, two sets of two-digit alphaand alpha-numeric fault codes will appear in theodometer display for a three second interval. Thefirst pair of digits represents a Diagnostic TroubleCode (DTC), or fault code for the instrument cluster.The second pair of digits is a counter for the numberof ignition key cycles that have occurred since thedisplayed DTC was set. The instrument cluster willcontinue to display additional sets of two pairs of digitsat three second intervals until all of the storedcodes have been displayed, which is again signaledby a code of “00” “00”. Refer to the Instrument ClusterFailure Message table for a description of eachfault code that the instrument cluster displays. If aninstrument cluster fault is displayed, use a DRBIIItscan tool to diagnose the problem. Refer to the appropriatediagnostic information.
Hi, yes it can. It flashes 5 times then comes up with "NO BUS". When we scan it, it comes up with a code P1687 - No Cluster Bus Message. We put a cluster from another truck that supposedly works... and nothing. It still starts though. What tests are there on the cluster by its self?
Wow! I will try this. Thanks! Awesome run down by the way.
Hey waynep712222, Thanks for all the info. Poor truck has been sitting for a while and I need to get it through inspection. Bought it from a damn kid for $5,700, about 7 months ago. Kid got me good. Found out it had a junkyard motor in it with #8 dead cylinder, plus a junkyard trans. (Not to mention it has a bad heater core). Replaced the motor, now the cluster is dead... but the cluster has been doing this off and on since I got it. It's not coming back on this time. I just want to get it past inspection. I will try all the tests you posted & get back to you. Thanks!
start under the hood... check the grounds from the engine to the firewall...check the negative battery connection to the fender..
check your email.. i send a link..
Hey Wayne,.. disconnected the ipod wire, took the after market stereo & harness completely out. Cleaned all interior plugs with electronic cleaner & blasted them out with 100 psi air. Cleaned the PCM Plugs (elc cleaner / air) and the ground (wire wheel). Re-checked all grounds & fuses. Cleaned ground behind kick panel. Next will be replace PCM & re-flash it. Keep ya posted. Thanks again.
did you find the manuals??