1999 dodge caravan the check engine light is on but no codes in pcm

The default gear for your caravan when there is a transmission issue is second gear. If it is stuck in second gear than the check engine light should be on. The OBDII code stored in the PCM should be a P0700. This code is to let you know there are transmission codes stored in the TCM. You will need a high end scan tool to get those codes. Once you know those codes you will have a much better idea of what is causing the transmission problems. Let me know if you have any questions and I'll do my best to answer them. Thank you for using FixYa.com!

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When "check engine" litgh tun on, the PCM (computer) is warning that some fault code is stored there. Autozone could scanned your PCM and show exactly what fault codes is there; if your O2 sensors was replaced, I assuming that they can see this codes... so, they reset and delete all codes stored there? Scanned the PCM after this change?

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If the noid light is working, the pcm is good. Why do you say it burned out? I would check ac voltage at each injector with engine running. If #2 has lower voltage than the others, you probably have a bad wire or connector.

CHECK ENGINE light turn on when any fault code or any maltfunction in there. I suggtes scanned the ECU or PCM to know exactly what fault code is stored, with this code number we could send additional details to solve it.

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The code P1698 is: No CCD messages from TCM. That means the communication between the Transmission Control Module and the Power Control Module is lost. Sometimes this happens when a PCM, or TCM is replaced without being flashed, a bad connection at the PCM, TCM, or a bad TCM. Hope this helps.

PO700 is a code telling you there are codes in the TCM of some late model cars where the Transmission control module has lost connection to the PCM the vehicals main computer , And basically it happens when the TCM has a issue within itself or the transmission that sets a code and it sends a request for the PCM to illuminate the SES or CHECK engine light.
PO740 is a chrystler specific code that involves your Tourqe Converter Clutch Circuit (specifically The TCC solenoid) this code if not repaired quickly could cause major transmission problems....slipping out of gear....not shifting from first to second properly and just all around trans problems...eventually leading to no shifting at all...I highly recommend fixing it soon.

radiator fan relay circuit.

check the pcm

OBD-II Trouble Code Technical Description
A P0020-023 code refers to the VVT (variable valve timing) or VCT (variable camshaft timing) components and the car's PCM (powertrain control module). That consists of an oil control valve (OCV), also called a solenoid valve and other components. Basically the check engine light and associated P0020-023 trouble code means that the voltage in the circuit has fallen below a set limit for a specific amount of time (varies by make/model/engine). Bank 2 is the side of the engine that doesn't contain cylinder #1.

Causes…
A code P0020-023 may mean that one or more of the following has happened:

• Faulty oil control valve (OCV)
• Open or short in the VVT/VCT circuit
• Open or short in the OCV / solenoid valve
• Damaged computer (PCM)

Possible Solutions
Some recommended troubleshooting and repair steps are:

• Carefully inspect the Bank 2 VVT/VCT system circuit wiring and connectors, repair as required
• With a warm engine, test the operation of the OCV, replace/repair as needed

P0700 is EATX code present. It simply means that the engine computer has noticed that the transmission computer has a dtc in it. This causes the Pcm (engine computer) to turn the check engine light on. You will need to have the TCM (trans computer) checked for codes to know what to diagnose.

error code P1776 - Replace rear solenoid switch

Likely both related The P1776 probably kicked off the P0700 notification.

Hope that helps! Happy Motoring!