Otc Monitor Obd Scan Tool Review

By Author: JD Durham
Total Articles: 42
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All of the OTC monitor OBD Scan Tools are what we now refer to as enhanced or manufacturer level data tools. This scan tool series was the dealer essential (required) tool for General Motors and Ford during OBD I. It was GM’s dealer essential scan tool until 1995 when the Vetronix unit replaced it. The retail version and the dealer versions differ only by cosmetics. Development continued by OTC until GM started switching the standard corporate protocol to
Controller Area Network (CAN). Development ceased in 2002 but the later model scan tools have the capability to perform OBD2 diagnostics until the 2006 model year on some vehicle brands.

These tools are almost indestructible. They were built for the rough work environment of the service areas. Later versions include a rubber protective wrapper to protect the units more. They were made specifically for the domestic vehicles of the time; GM, Ford, and Chrysler. Later OTC added the capabilities to scan Japanese made vehicles.

The ...
... early version was called Monitor 85, which was introduced with 1982 model year GM vehicles. This version had most of the sensors / switches (PIDs) cross referenced on the face of the tool. This tool had the cables hard wired and the software was permanently programmed into the tool. It had a zero upgrade path. The model 2000 is also hard wired.

Monitor 85 included an adapter to access the 1980 and early 1981 5 pin ALDL connector, a small operations instruction manual, and 3 specifications cards. All require the mechanic to input the information to properly identify the vehicle. The Monitor 85 can service vehicles until about 1988, but you must ‘lie to the tool’ or purposely misidentify the vehicle and engine.

The later versions 2000, 4000, 4000E and the Enhanced obd scan tools were equipped with the ability to update or add functions via a software cartridge, different cables, and cable inserts. Most are capable of operating as both an OBD I and OBD II scan tools as well as transmission, air bags, antilock brakes, and air conditioning diagnostics. These later versions included a better instruction manual; some had instructional video tapes, Technical Service Bulletin manuals, and PROM ID manuals.

These later versions were built to interface to a PC so that remote assistance could be rendered or use the OTC GTI graphics software package for those oriented more toward graphics diagnostics.

They have LEDs on the face for the PRNDL switch, Open/Close loop operation, O2S (rich / lean), TCC, AC, and test state. There is an LCD display that presents information and data that the mechanic needs. This is in the form of 4 lines of scrollable information or up to 8 sensors / switches (PID) at one time and graphic notations as well. These PIDs can be changed as needed. They also include a help function, information about the abbreviations used, expected ranges of the data, specifications, and some have the TSBs either displayed or referenced.

The later versions were capable of multiple languages and guided path diagnostics. Guided path diagnostics is referred to as PathFinder. This PathFinder feature is very useful for the beginning diagnostic mechanic to keep them organized and focused.

They include the capability of data recording in a series of frames. Up to 61 frames are divided before and after the record function was pressed. This allows a mechanic to test drive the vehicle and when he experiences an event to press the record button. That data leading into and after the event can be viewed later at the shop. It has the capability of storing several vehicle data sets and marking those for reference later.

These tools have the ability to help the mechanic today with many things, including resetting the TCM of vehicles to eliminate damage to them caused by driving them without being set properly.

The biggest problem with these tools was not the tools, but OTC’s marketing division. They frequently stated that coverage was more than it was. Eg: they would state 2001 coverage, which mechanics would interpret as all 2001 vehicles when in fact it was only a few models or sub models for 2001. This was and still is the standard practice in the industry for many corporations.

These were very expensive for the professionals that originally purchased them. As you can tell these scan tools have lots of help and can be very beneficial to the mechanics of today. Therefore, if you find one of the later 4000, 4000E or Enhanced obd scan tools with lots of accessories, cables, modules, training materials and books…just add it to your toolbox! It is a good investment in not only diagnosing and repairing cars, but it can educate you as well.

Remember the limitations of the previous models and only purchase those if you truly have a need for those older vehicles.

Copyright © 2012 JD Durham

JD Durham is a World Class Technician, an Automotive Hall of Fame honoree with 45 years experience in the automotive service and repair industry and a staff writer at Straight Talk Automotive. You are encouraged to visit for more information on OBD2 Scan Tool, and OBD Bluetooth scan tool, also accept this invitation to join our FREE members only area and access great free resources.