Best scan tool to purchase?

Hi,

Scan tools come in different designs with different abilities. The question is cost and need. If you want something very simple, you can get any scanner at usually under $40.00. If you want one that can read the can-bus, they are a little more. Also, there are bidirectional scanners that are designed to communicate with the vehicle and have the ability to actuate different electrical components.

Let me know what you need to do and the cost you would like to stay within. I'll try to check into it for you.

Take care,

Joe

It depends on what else you want to do with it. The dealer's scanner was the DRB2 for models up to 1995. It required a cartridge for the model you were working on. There were dozens of cartridges, but by 1994 there was a "Supercartridge" with a yellow sticker that matched the color of the service manual covers for that year. That cartridge was also used for 1995 models since nothing changed between those two years. That one cartridge covered all models back to 1983.

For a 1999 model, the dealer's scanner was the DRB3. You can find both of these on eBay. Depending on the year it was built, it will work directly on all Chrysler models back to 1996 or 1998. The first models this went obsolete on was the 2004 Durango / Dakota. The last models it worked on were some 2008 Jeeps. No cartridge is needed with the DRB3, but you can insert an extra cartridge to make it work on models from 1983 through 1993. A different add-on cartridge is available for 1994 through 1997 models. The nice thing about that one is it allows you to do emissions testing on all brands of vehicles sold in the U.S. Starting with '96 models. For that reason, a lot of independent shops bought them. Today, since they are obsolete for the newer stuff, many of those shops want to sell theirs to buy something newer. A used DRB3 will typically bring around $2000.00, but the cost should be coming down now as there's less call for them. They had an entire kit available online for $6200.00. You don't need all the extras that came in that kit. There's just one cable for the '96 and newer models, and another cable for use with the "Supercard 2" if you want to use it on '95 and older models. I've had one of these for many years for all of my older vehicles.

If you're made of money, look at a Snapon Solus Edge. When you buy these new, they charge extra for European import coverage, and extra for Asian imports. Then they charge a huge fee for every annual update. You do not need to buy those updates as long as it is updated new enough to cover everything you want to work on. Another sore point is if you find one that is, say, five years out of date, you have to buy every year if you want to bring it current. To say that a different way, mine is updated through 2018. To make mine current, I'd have to buy the 2019 update before I can buy the 2020 update, etc. That can work in your favor. By the time a shop lets theirs get five or six years out-of-date, it would be less expensive to just buy a brand new one with the latest updates. Being so far out-of-date lowers the value to other shops. The last time I looked, these were on eBay for as little as $700.00 updated through around 2014 models.

A better option if you want to go with an aftermarket scanner is something by Autel. One of our other experts bought one about a year ago and told us he is very happy with it. Based on his glowing testimonial, I bought one about a month ago, but it needs to have the scanner software downloaded over the internet. I haven't done that yet. The fellow I bought mine from on eBay has hundreds of them listed covering around a dozen different models. I think they have something that might satisfy you for a little over $400.00. I got a more expensive model that is supposed to let me program key fobs and some computer modules. This appears to be a very high-quality unit with tough cases and padding.

Other experts may chime in with their recommendations too. Typically no aftermarket scanner will do everything the dealer's scanner will do, but the aftermarket ones will do it on more brands and models. I only own Chrysler products, but I use my Solus Edge more on friends' cars. My scanner gets the most use on Fords and on GM trucks. A friend has this same scanner, but he keeps his updated. He has spent three times more on those updates alone than I paid for my scanner, (used), in 2018.

Be aware too, there's a lot of very inexpensive code readers available online that are far superior to what was out there just a few years ago. The older ones could only read codes in the Engine Computers, and if they could display live data, the screens updated painfully slowly, as in once every couple of seconds. I found one recently that can read codes in a number of other computers including Air Bag and Anti-Lock Brakes, and the live data displays refresh very quickly. Some of these cost less than 20 bucks. Most of these inexpensive units just read and display data. Full scanners are "bidirectional", meaning you can talk back to the computers and command them to run tests and do other things like turn relays and solenoids on and off.

Let me know if you have other questions or if you need help setting something up. Most of the newer scanners just get plugged in and you start punching buttons. Some, like the Solus Edge include code tips and troubleshooting steps built in so you don't have to find a service manual for every problem.

Probably not. The last models it worked on were some 2008 Jeeps. I don't know how new it went on the minivans.

I just checked on eBay and was surprised to see the DRB2 and DRB3 are bringing a lot more than the last time I looked about a year ago. Some are listed for well over $4000.00. The better alternative among those I listed is the Autel scanner. I haven't installed the scanner software yet, but I've talked with a few people who have them, and they're all very happy.

Whatever you look at, look at the computer languages they use. The '95 and older models used the "OBD1" language. That stands for "On-board diagnostics emissions system, version 1". Every manufacturer had their own proprietary cable connector anywhere on the vehicle.

All '96 and newer models sold in the U.S. Use the OBD2 system. (On-board diagnostics version 2 emissions system). They all used the same connector under or near the steering column, but some terminals were made available for use at the manufacturer's discretion or needs. This is the first system where the very inexpensive code readers showed up.

The next step was the "CAN Buss" system. That stands for "Controller area network". All the computers communicate with each other over a pair of wires. The scanner uses that too. There can be two, three, and even four separate buss systems on a vehicle. They run at different speeds as needed by different systems. On these vehicles, the scanner connects to two of the data busses to access all of the computers.

To my knowledge, the newer scanners will talk on the OBD2 systems and on the CAN Buss systems, but that should be specified in the listing information so it will work on the vehicles you need it for. If you find something else, like the Solus Edge, it works on all models the software is updated for, but if you use it on '95 or older models, you'll need a different cable and the connector, (they call it an adapter), that fits the specific vehicle. I found a European kit with six or seven connectors a few years ago on eBay for less than $100.00. A lot of individual connectors are listed for less than 20 bucks each.

P1391 - Intermittent Loss of CMP or CKP

I haven't looked with my Snapon scanner, but my DRB3 lists both of these sensors with a "No" or "Present" during cranking on the "live data" menu. Aftermarket scanners have some similar means of displaying that information. Leave the scanner connected and take it with you on a test drive. If you leave it on that screen, you might be able to see which sensor switches to "No" in the brief time the engine is coasting to a stop. Otherwise just watch them when you crank the engine. One will not switch to "Present". That's the circuit to diagnose.

Also be aware these fault codes never say to replace a part or that one is defective. When a sensor or other part is referenced in a fault code, as they are in code P1391, it is only the cause of that code about half of the time. First we have to rule out wiring and connector terminal problems, and mechanical problems associated with that part.

There is something you might consider as far as mechanical problems. Back in the '90s when I was working at the dealership, I was their suspension and alignment specialist, but to help out the other guys, in ten years, I replaced 13 transmissions. These were all on front-wheel-drive models, and all required removal of the crankshaft position sensor. When reinstalling them, the air gap is critical. OEM-style sensors have a thick paper spacer on the end to set that gap. It slides off the first time you crank the engine, but by that time, its job is done. Many aftermarket sensors have a thin plastic rib molded to the end to set that air gap. It can wear down over time. When reinstalling a used one of that style, you're supposed to cut the remaining part of the rib off, then use a new paper spacer.

Being the cheap fellow I tend to be, I started cutting those paper spacers into four pieces to use on four transmission jobs. That saved three customers ten cents each. By the time I got to the 13th job, I was too arrogant and didn't bother to use a spacer. I just shoved the sensor all the way in, pulled it back the approximate mount, then tightened the mounting bolt. Everything went fine at first, but that vehicle came back two weeks later with intermittent stalling. The mechanic working on it replaced the crank sensor and the problem was solved. Everyone just assumed the sensor was failing, especially since that is how they often act. I have to wonder if the stalling was due to my not setting the air gap correctly.

On your engine, the crankshaft position sensor uses a different style of mounting ear that sets the air gap automatically. The camshaft position sensor is a different story. In the photo below, my blue arrow is pointing to the oval mounting hole that allows for the adjustment. The red arrow is pointing to the paper spacer that sets the air gap. When you installed the replacement sensor, if the paper spacer wasn't there, or the sensor didn't get pushed in all the way, the air gap can be too big. That will decrease the size of the signal being developed, possibly to the point the Engine Computer can't read it. In response, it turns off the automatic shutdown, (ASD) relay. That relay sends 12 volts to the injectors, ignition coils, alternator field, and fuel pump or fuel pump relay.

Also look at the terminals in the connectors for both sensors. Sometimes one gets pushed out and makes a poor contact with its mating terminal. The female terminal can become "spread" too, especially when a voltmeter probe is stuffed into it. That makes it too wide to make solid contact with the mating terminal. Often you can identify those by wiggling the connectors while the engine is idling.

Don't waste your valuable time testing ignition coils and such. They're going to be shorted, (very rare), open, or good. Even if one fails, you'll get a fault code for a single-cylinder misfire. You know all the coils aren't going to fail at the same time. One bad coil won't cause intermittent stalling. If you were to force a short by jumping the two primary wires together while the engine was running, it would blow a fuse, then the engine would not be able to be restarted later.

Crankshaft position sensors and camshaft position sensors on all car brands commonly fail by becoming heat-sensitive, then they work again after cooling down, typically for an hour. That type of failure usually doesn't occur with a new sensor, but anything is possible.

Now let me go in a different direction. One of the new parts you listed was the battery. By disconnecting it, you will have an idle speed that's too low until the Engine Computer relearns "minimum throttle". You may not get the engine to run unless you hold the accelerator pedal down 1/4". Even if it does start and run, you won't get the nice "idle flare-up" to 1500 rpm at startup, and it will have a tendency to stall at stop signs. Due to the fault code you have, this likely doesn't apply, but if the stalling only occurs when you're slowing down or stopped, see if the engine can be restarted right away by holding the accelerator pedal down a little. If that works every time, the conditions needed to cause the relearn to take place are met by driving at highway speed with the engine warmed up, then coasting for at least seven seconds without touching the pedals.

:) thank you for saying that, we appreciate it.