Question about 1998 GMC Savana

Open Question

No communication out of the ecm when put scan tool on it telling me the key isnt on

Posted by on


Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

2 Answers

2006 armada. can't mmunicate with any computers on vehicle with scan toolno blown fuses

get the correct scam tool with the right protocols for reading the codes
the cheaper tools --up to $500 will only read certain makes of cars
some only read European makes , some only Asian cars and companies like GM need a special scan tool to read their computers
makes like Nissan have a switch in the side of the ECM which needs to be turned on to get the codes reading on a scan tool
scan tools that have the capability to read all cars cost upwards of $15,000.00

Nov 09, 2017 | 2006 Nissan Armada

1 Answer


Where are you coming up with this ?
ISO 9141 and KWP 2000 this is a communication protacoll. when the scan tool is plug into the OBD port it uses a set amount of communication dialog to communicate with the ECM, Majority of time when a scan tool can not communicate with the vehicles ECM ,

Apr 08, 2017 | 2008 GMC Envoy

1 Answer

Lost current communication with fuel injector control module

Lost current communication with fuel injector control module ? Would you like to try and explain that a little better ? Lost communication with Engine computer PCM/ECM ? A scan tool won't talk with the PCM / ECM ? What type scan tool ? Can your scan tool talk with any other control module on the vehicle ? BCM , EBCM , SRS etc... if you know what those are ? Or current , are you talking about electrical current ? I know I only have thirty years experience as automotive Tech . I need terms that I can relate to .

Dec 01, 2016 | Cars & Trucks

1 Answer

Why won't it start?

check that the battery terminals are shiny clean along with the battery posts as the dark grey/ black condition may be too a high a resistance for the battery current draw
try using a scan tool to reset the ECM program

Sep 17, 2015 | Cars & Trucks

1 Answer

I have a 2006 Chevy uplander, 3.5l, and when I turn the key to on position only the check engine symbol light's up on the instrument cluster and when turning key to cranking position nothing happens.

This is what would be done at the dealer or any good repair shop !
Perform the following preliminary inspections:
Ensure that the battery is fully charged. Refer to Battery Inspection/Test .

Ensure that the battery cables are clean and tight.

Inspect for any open fuses.

Refer to Power Distribution Schematics and Electrical Center Identification Views .

Inspect the easily accessible systems or the visible system components for obvious damage or conditions that could cause the symptom.

Ensure that the grounds are clean, tight, and in the correct location.

Refer to Ground Distribution Schematics and Power and Grounding Component Views .

Inspect for aftermarket devices that could affect the operation of the system. Refer to Checking Aftermarket Accessories .

Search for applicable service bulletins.

Did you find and correct the condition?
System OK
Go to Step 2


Install a scan tool.
Does the scan tool power up?
Go to Step 3
Go to Scan Tool Does Not Power Up


  1. Turn ON the ignition, with the engine OFF.
  2. Attempt to establish communication with all of the control modules on the vehicle. Refer to Scan Tool Does Not Communicate with Class 2 Device for the modules you should expect to observe.
Does the scan tool communicate with all of the expected vehicle control modules
To ensure that retained accessory power (RAP) mode is inactive, if equipped, open the drivers door during the following step.

The engine may start during the following step. Turn OFF the engine as soon as you have observed the crank power mode.

  1. Access the Power Mode parameter on the scan tool.
  2. Rotate the ignition switch, operate the ignition mode switch, through all positions while observing the Power Mode parameter. Refer to Body Control System Description and Operation for a list of the power mode states that correspond with each switch position.
Does the Power Mode parameter reading on the scan tool match the ignition switch position for all switch positions?
Go to Step 5
Go to Power Mode Mismatch


Attempt to start the engine.
Does the engine crank?
Go to Step 6
Go to Symptoms - Engine Electrical


Turn the ignition to the START position.
Does the engine crank?
Go to Testing for Intermittent Conditions and Poor Connections
Go to Step 3


  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. Verify that the transmission is in Park or Neutral.
  4. With a scan tool, observe the IMS parameter in the powertrain control module (PCM)/engine control module (ECM) data list.
Does the scan tool display Park or Neutral?
Go to Step 4
Go to Range Selector Displays Incorrect Range


  1. Turn ON the ignition, with the engine OFF.
  2. With a scan tool, observe the Starter Relay Command parameter in the PCM/ECM data list.
  3. Turn the ignition to the START position.
Does the scan tool display Yes?
Go to Step 6
Go to Step 5
With all the modules on your vehicle you really need to start with a professional grade scan tool to see if all are communicating .

Aug 17, 2015 | Cars & Trucks

1 Answer

Why scan tool doesn,t connect to truck.

ecm has been replaced????? was it programmed ?

Sep 27, 2017 | 2003 Chevrolet Avalanche

1 Answer

Obd code U1041

Codes U1XXX (where XXX stands for several possible numerical digits, 001 - 254) are communications fault codes. The first part (U1) tells you that there is a communication problem with one of your many onboard control modules. The second part (XXX) or in your case, (041) tells you which module is not communicating. It can vary from year to year, model to model. so without knowing the year and model of the vehicle we are talking about, I cannot tell you which one.

In any case, there is a module that is not communicating with the other modules that are sharing information through the Class 2 serial data circuit. One module uses U-codes to tell on the other modules. For instance, If you got the U1041 code out of scanning the Engine Control Module, you can bet that the Engine Control Module is not having a problem communicating. If it was, you would get a non-communication fault from your scan equipment and the ECM would not tell you anything. Instead, the ECM is telling on the module that is not communicating properly .

I like to call these codes the 1-800 codes...THE PHONE LINE IS DOWN... lol ;)

Nov 24, 2010 | Chevrolet Silverado 1500 Cars & Trucks

1 Answer

1997 breeze is shooting codes 12 46 43 55

OBD Code 12 - No Distributor Reference Pulse (Diagnostic Test Active) The Engine Control Module-ECM uses the distributor reference pulse to calculate the engine speed. On newer engines, the Crank Shaft Position Sensor performs this function.

  • When flashing the Check Engine Light to read codes, code 12 will always display first, indicating the diagnostic system is active
  • The engine will not run with a "hard" code 12 set
Common Problems:
  • Chances are you will never need to diagnose a code 12. Rather, the problem would be a crank, no-start condition.
  • If code 12 does not flash, that would indicate a communication problem with the ECM.
  • Code 12 does not show when reading codes with a scan tool. If there is a communication problem, the scan tool will let you know.

OBD Code 46 - Pass-Key II System Error - Circuit out of Frequency Range The ECM receives a signal from the Pass-Key module. When the correct signal is received, the ECM will allow the engine to start and run. Please review the RepairPal article on the GM Pass-Key Anti-theft systems for more information.

  • Engine may not start
Common Problems:
  • Faulty ignition lock cylinder

OBD Code 43 - Knock Sensor error The ECM receives a signal from the Knock Sensor based on the amount of engine ping detected. The ECM uses information from this sensor to help calculate fuel delivery and spark timing.

  • Engine ping
  • Lack of power
Common Problems:
  • Faulty Knock sensor
  • Poor connection at Knock sensor

OBD Code 55 - End Test.

Hope ehit help (remember comment and rated this).

Jul 22, 2010 | 1997 Plymouth Breeze

1 Answer

Need information on checking for no communication for ecm to scan tool. 2000 Oldsmobile Alero 3.4 L.

If the car is running fairly normally but just won't talk to the scan tool then what I usually find is that there is a blown fuse that powers one of the pins in the OBD-II scan tool connector. I don't have a diagram of which fuse it might be but that's where I would start looking. My scan tool gives me the dreaded "no data" message anytime one of these has lost power to the connector. You could have other issues including a faulty ECM but it's pretty rare for that to happen.

Jun 11, 2010 | 2000 Oldsmobile Alero

Not finding what you are looking for?
1998 GMC Savana Logo

Related Topics:

149 people viewed this question

Ask a Question

Usually answered in minutes!

Top GMC Experts


Level 3 Expert

76649 Answers


Level 3 Expert

1311 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22219 Answers

Are you a GMC Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides