Car computer not communicating. . Oct 29, 2018 · Disconnected Wires – The wires connecting the OBD II port to the vehicle’s computer may be disconnected or damaged, preventing communication. This problem can stop you from diagnosing check engine lights, running emissions tests, or monitoring your vehicle’s performance. (RESOLVED - Click To View) The smog technician says my car will not communicate with the smog machine. Using an OBDII scan tool to communicate with vehicle ECU is generally considered pretty straightforward task. Jun 13, 2025 · Is your car scanner showing power but refusing to read any data? You’re dealing with one of the most frustrating diagnostic issues—when your OBD2 port has power but no communication. Courtesy of a SNAPON document If the scan tool does not receive data from an OBD II vehicle TEST 1: Connect the positive DMM lead to DLC pin 4 and the negative DMM lead to the negative battery terminal, using jumper wires if necessary. Learn troubleshooting tips that actually work. Feb 2, 2026 · Is your OBD2 scanner not linking to your car? Discover common causes & troubleshooting solutions to fix OBD2 connection issues, blown fuses & faulty wiring Feb 11, 2021 · Resolve connectivity problems with your car's OBD II scanner and its computer. No communication with the car computer (ECU)? This guide will show you how to diagnose no communication issues step-by-step. In this guide, we will learn the reasons for unresponsive OBD and how to fix the OBD communication failure issue step by step. By checking the OBD-II port, verifying the power supply, updating the scanner software, confirming compatibility, inspecting the ECU, and addressing software conflicts, you can solve the problem. 1 Volts Scotty Kilmer, mechanic for the last 48 years, shows how to fix a broken car the won't communicate with a scan tool so you can't get any information on the problem. Why Won’t My OBD2 Scanner In this video I explain why your ecm/pcm is not communicating with scan tool or the ecm is not communicating with the tcm, bcm, abs module etc If you're receiving U0001, U0010, U0100 diagnostic Sep 26, 2021 · It is considered manipulation, and it may prevent the car from communicating with the OBD2 testing equipment during the examination. Dead Battery – If your car battery is dead or low, the OBD II scanner may not be able to establish a connection. If your OBD is also not responding/connecting, you can try these tips to solve the issue. What can I do? Apr 29, 2022 · The other type of communication issue could be with a sensor or actuator. With these types of errors, you can communicate with a module, but the information from a sensor is missing or implausible. However, on some rare occasions certain issues can make connection and communicating to the system troublesome. If it doesn’t work, the problem is likely with your scan tool. OBD2 scanner not communicating? See the top causes, quick fixes, and when to send your ECU/PCM to SOLO Auto Electronics for expert diagnosis and repair Oct 29, 2021 · The other type of communication issue could be with a sensor or actuator. May 16, 2024 · ANCEL scanner for car are the top choice for many auto mechanic. How to fix OBD connection [OBD no communication] When your OBD isn’t working, the first step is to determine if the problem lies with your car or the scan tool. An experienced automotive technician understand that communication issues can be caused by various Jun 3, 2024 · OBD2 scanner not connecting to ECU? If your OBD2 scanner powers on but won’t connect to the ECU or reads no codes, this guide explains why it happens and how to fix OBD2 connection issues step by step. Jun 21, 2024 · Fixing the issue of your vehicle scanner not connecting to the ECU takes a step-by-step approach. In short, if both the DLC and the fuse have no problems, this one is likely the reason why your OBD2 won’t communicate. Sometimes, it happens due to OBD communication failure. Related Reading: Why My Car Shuts Off While Driving? Possible Causes There are a few reasons why your OBD II scanner may not be able to communicate with your vehicle. Faulty Scanner The first possibility is that your OBD II scanner itself is faulty. Do not connect to body or chassis ground but to the battery terminal directly With the ignition on, voltage drop across the ground terminal should be 0. Jan 22, 2026 · OBD has power but no communication? Learn what causes this issue, how to troubleshoot it, and when to contact SOLO’s auto computer repair specialists. We would like to show you a description here but the site won’t allow us. Test the scan tool on another car: If it works on another car, the issue is with your car. What to Do When Your OBD2 Won’t Connect? Aug 14, 2022 · Suppose you inserted an OBD2 scan tool in your vehicle, but it doesn’t connect with your device. cij vnt yqt sdo tjb iel mgo msn cij mvo rkt sje uoy tsy dcq