Dec 2, 2013 · Hi, just found out about an easy way to test your PCM if you suspect its junk. 1-Verify that there is battery voltage going in to the PCM at pin connectors 2 and 22 on the black connector. …

May 2, 2016 · How can I test if PCM is good??These are the symptoms...crank,no start..5V reference voltages at TPS and mass air sensor...Speedo jumps to 80 when turning key to on.slight hesitation …

Aug 28, 2014 · To reset your car's computer after replacing O2 sensors and clear the check engine light for an inspection, a common recommendation is to drive for 60-100 miles. This allows the car's …

Jul 10, 2018 · If not, you should be able to test the computer data lines with a multimeter. Put the black lead on the OBD connector pin 4/5 and the red on pin 2 (J1850+). When you turn the key from the …

Nov 5, 2013 · If your 1997 Jeep TJ cranks but doesn't start and you suspect a bad ECU (Engine Control Unit), here's how to troubleshoot: * **Scanner Connection:** If the ECU is bad, it might not connect to …

Dec 30, 2019 · The new computer was programmed to my VIN and the SKREEM (security system) was completely removed from the computer. So in my understanding, it should not be a security issue …

Sep 30, 2025 · Not a good scenario when it shifts this way. Its a simple test to perform to make sure your computer reads close to the thermostat. Worth the time in my very humble opinion. Thermostats …

Aug 14, 2025 · Connect a 0-60 psi (0-4.2 kg/cm ) fuel pressure gauge to the pressure test port fitting on fuel rail. 2) Remove vacuum line from fuel pressure regulator. Start vehicle and note gauge reading. …

Jul 9, 2011 · To reset your Jeep Wrangler's ECU (PCM) and clear any stored codes, the most reliable method is to disconnect the battery for at least 8 hours. This will reset the computer to its default …

Jul 9, 2019 · Here is how to test this. Get yourself a test light. Not one of the computer safe ones, get one that has the incandescent bulb. I am assuming the power to the coil works otherwise the engine …