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98 pontiac transport no communication with scan tool

Check engine light

Posted by Anonymous on


6 Suggested Answers

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

A 6ya expert can help you resolve that issue over the phone in a minute or two.
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Posted on Jan 02, 2017


SOURCE: 2003 Caravan No Crank, 3.3L

This is a bad PCM. Try to disconnect the security system first and if it still does not start then it is the PCM.

Posted on Aug 11, 2008

  • 335 Answers

SOURCE: obd1 scan tool will notaccess

A couple of ways to check and see if the computer is ok first:
check engine light must come onwith they in on position
The fuel pump must run for two (2) seconds with the key ON
There must be a 5 volt reference at sensors like map, TPS
Must communicate with scan tool
The ORANGE wires at the computer are you power input wires one has 12V all the time this is your KEEP ALIVE MEMORY
one is 12 with the Key on you MUAT HAVE VOLTAGE AT BOTH
Check the computers Ground most are out under the hood and are brown wires
Try the GM TAP TEST this is a factory authorized test with the computer connected and you verified all of the above SLAP the computer with the open hand firmly not too hard but firm see if anything changes,
Do not disconnect the battery you will erase all the codes!
Please contact me if you need any additional information.
If you find the information provided helpful please give me a good rating

Posted on Aug 14, 2008

  • 117 Answers

SOURCE: 2003 chevy trailblazer ecm not reading scan tool

your underhood fuse block contains a fuse for the cigar lighter. this also powers the scan tool make sure it is not blown. chk pin 5 at data link connector for good ground pin 2 for power

Posted on Nov 15, 2009

  • 396 Answers


This might help you to better understand the EVAP system and help diagnosing the code that was set. Basically there is a leak and you need to find it. Could be very hard to find without a smoke machine. I would take it into a shop to have it tested with a smoke machine and go from there. Some people might say to just replace the gas cap, but if that's not what it is, there is $20-30 wasted, when it could have been put towards an actual diagnoses that will actually help you to fix the problem DTC P0455 System Description
The control module tests the evaporative emission (EVAP) system for a large leak. The control module monitors the fuel tank pressure (FTP) sensor signal to determine the EVAP system vacuum level. When the conditions for running are met, the control module commands the EVAP canister purge solenoid valve OPEN and the EVAP canister vent solenoid valve CLOSED . This allows engine vacuum to enter the EVAP system. At a calibrated time, or vacuum level, the control module commands the EVAP canister purge solenoid valve closed, sealing the system, and monitors the FTP sensor input in order to determine the EVAP system vacuum level. If the system is unable to achieve the calibrated vacuum level, or the vacuum level decreases too rapidly, this DTC sets. Hope i didn't confuse you.

Posted on Feb 02, 2010

  • 957 Answers

SOURCE: Reset Check engine light on 1993 Geo Tracker

A 1993 Tracker will have OBD1 technology. Just unplug the battery for 5minutes and plug it back in. If the light persists You will have to find out and repair the problem that your cars computer believes it has.

Posted on May 12, 2010

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Have a Honda Accord 2008 v6 chk engineer light on code iso 9141 meaning?

Trevor, I believe this is not a code, iso 9141 is communication protocol/ communication speed, When the scan tools make a connection to the OBD port it matches the communication speed at which your ECM communicates with the scan tool. If that is all you are seeing for a code and your engine light is on, try a different scan tool. Check the attached links,instruction and guides, Good luck
"I hope this helped you out, if so let me know by pressing the helpful button. Check out some of my other posts if you need more tips and info."
On board diagnostics

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2002 chevy silverado trys to stall in any condition sometime it will stall. all dash light will come on. starts right up.

Is check engine light Lit ? You should have all the computers on the vehicle check for DTC'S - diagnostic trouble codes ! Check the battery an all connections !
Diagnostic Starting Point - Engine Electrical
Begin the system diagnosis with the Diagnostic System Check - Engine Electrical . The Diagnostic System Check will provide the following information:
The identification of the control module(s) which command the system.

The ability of the control modules to communicate through the serial data circuit.

The identification of any stored diagnostic trouble codes (DTCs) and their status.

The use of the Diagnostic System Check will identify the correct procedure for diagnosing the system and where the procedure is located.
Diagnostic System Check - Engine Electrical
Test Description
The numbers below refer to the step numbers on the diagnostic table.
Lack of communication may be due to a partial malfunction of the class 2 serial data circuit or due to a total malfunction of the class 2 serial data circuit. The specified procedure will determine the particular condition.
The symptom list in Symptoms will determine the correct diagnostic procedure to use.
The presence of DTCs which begin with "U" indicate some other module is not communicating. The specified procedure will compile all the available information before tests are performed.

Did you perform the Battery Inspection/Test?
Go to Step 2
Go to Battery Inspection/Test

Install a scan tool.
Does the scan tool power up?
Go to Step 4
Go to Scan Tool Does Not Power Up in Data Link Communications

Important: The engine may start during the following step. Turn OFF the engine as soon as you have observed the Crank power mode.
Access the Class 2 Power Mode in the Diagnostic Circuit Check on the scan tool.
Rotate the ignition switch through all positions while observing the Class 2 Power Mode on the Scan Tool. Refer to the Serial Data Power Mode table within the Body Control System Description and Operation in Body Control System for a list of the power mode states that correspond to each ignition switch position.
Does the Class 2 Power Mode parameter reading match the ignition switch position for all the selected positions?
Go to Step 4
Go to Power Mode Mismatch in Body Control System

Turn ON the ignition, with the engine OFF.
Attempt to communicate with each module on the class 2 serial data circuit:
• The body control module (BCM)
• The driver information center (DIC)
• The instrument panel cluster (IPC)
• The powertrain control module (PCM)
Does the scan tool communicate with any module on the class 2 serial data circuit?
Go to Step 5
Go to Scan Tool Does Not Communicate with Class 2 Device in Data Link Communications

Select the Display DTCs function for each module. If using a Tech 2, use the Class 2 DTC Check feature in order to determine which modules have DTCs set.
Record all of the displayed DTCs the DTC status and the module which set the DTC.
Does the scan tool display any DTCs?
Go to Step 6
Go to Symptoms - Engine Electrical

Does the scan tool display any DTC beginning with "U"?
Go to Diagnostic Trouble Code (DTC) List in Data Link Communications
Go to Step 7

Does the scan tool display any DTC beginning with "B"?
Go to Diagnostic Trouble Code (DTC) List in Body Control Systems
Go to Diagnostic Trouble Code (DTC)

Oct 28, 2015 | Cars & Trucks

1 Answer

How do I fix a serial 2 data link malfunction on a 4 cylinder 99 sunfire

Hey John ! how's it going ? How do you know you have a class 2 data bus problem ? Need some more info ! Do you have a scan tool ? Can't communicate with the PCM ? Have a check engine light on ?
You may access 2 data lines with the scan tool. The serial data line UART (circuit 800) allows the following components to communicate via serial data:
The scan tool

The powertrain control module (PCM)

The instrument panel cluster

The sensing diagnostic module (SDM)

The electronic brake control module (EBCM)

The serial data line class 2 (circuit 1807) allows the scan tool to access directly the PCM in order to read emissions-related information. The scan tool gains access to both data lines through the data link connector (DLC). You may then monitor or control system operations for diagnostic purposes.

Mar 08, 2015 | 1999 Pontiac Sunfire

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2003 montana, not cranking no spark

Have you are dealership check with a scan tool to see if you have a cam sensor, or crank sensor problem. Without these 2 you have no communication with the ECM

Jul 04, 2014 | 2003 Pontiac Montana

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Check engine light

sometimes you don't put the gas cap on properly, the sensor will put check engine light on. Go and check the gas cap.

Oct 27, 2013 | 2006 Pontiac Grand Prix

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If your tryi g to use an OBDII code reader you. At not be able to get them to work. If your scan tool cost less than $500 dollars it may not work. If you have a high end scan tool, more than $3,000 dollars than that should work.

Apr 13, 2013 | Cars & Trucks

1 Answer

No fire on 98 transport

recheck all eletrical connections on the engine also recheck for pinched wires and coputer ground wires.

Jan 13, 2010 | 1998 Pontiac Trans

1 Answer

98 montana transport van

Sometimes it is easier to loosen wiper motor assembly and move it out of the way,then remove upper engine mounts "they look like a dog bone" and rock the engine forward.

Aug 15, 2009 | 1997 Pontiac Trans Sport

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Check engine light on '98 pontiac montana comes on then goes off again several times. Is this common? One place said it is likely an oxygen sensor, but why woiuldn't it stay on?

this is common, it is most likely an O2 sensor is going bad, have the trouble codes stored in the system computer checked by a Kragen or Autozone parts store,the test is free.

Apr 09, 2009 | 1998 Pontiac Trans

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i would not worry about the code 47 the code 46 is a pcm communication problem that is what turned the light on the power steering usually will not turn the light on i would check all my fuses first for the code 46 is there any other noticeable problems like with heater or a/c that may help me help u solve the problem

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