What OBDII scanners will read a 1999 P1 v70 and where is location of its ecu

 

Many will advise to get the Volvo (VADIS) system loaded onto a laptop. In all likelihood you want something cheaper.
A scanner which connects with a CANBUS system will work. Only the cheapest of the cheap will be non-CANBUS.
You probably want to use this scanner on other cars now and into the future.
Consider one with advanced features like ABS and SRS clearing capacities. You'll want to read transmission temperatures and other values in future vehicles too.

What's available in the UK often differs from what we have here.

We got my BIL an Autel "Diaglink". I believe it corresponds to whatever they call a model 1340. It's good for him.
Frankly, as time goes on they keep consolidating more features in lower priced units.
Don't buy without going to a particular company's website to make sure you get the most for your money. This is done after you establish your budget.
You needn't go into debt to buy a scanner you cannot use.
Consider buying locally as you must make sure a code reader connects with your car. Plus, electronics either suffer infant mortality or last a long, long time. It'd be nice to have a shop to walk into if a return is necessary.

I believe the ECU is in the squarish box forward in the engine compartment. IT'll be on the vehicle's right side (left side as you look into the engine bay).
It's good to inspect said box for water intrusion. There's an air vent hose which reaches forward from it. Sometimes it's missing.

 

Thanks for advice. I will look for ecu where you described. I have had three different diagnostics systems on the vehicle and all three failed to read the car coz they only work on 2000 model years onward. I am trying to check for fault codes that would indicate a crank position sensor fault (in wiring or sensor) or cam pos sensor fault. I suspect the problem may be with the crank sensor or cam sensor (or there respective wiring) for this reason - after the motor developed the fault of dying shortly after firing, then, after a period of consistently dying would start running normally again for an indefinite time, before again returning to continually dying for a period, after which it recovered yet again. While the schizophrenic motor was in the running normally state I deliberately brought the wire from the crank position sensor and the wire from the cam position sensor together and the instant the two wires came together the motor died in the exact same way it had been dying after firing when the dying-after-firing fault was present! I was 100% certain I had found the problem and it was interference from the crank sensor wire and the cam sensor wire confusing the ecu. I rerouted the wires to keep them apart and insulated each wire with rubber tubing from spare vacuum pipes to make certain there could be no more interference. After this the motor continued to reliably fire and continue running normally for every single one of several tests which convinced me the fault was totally fixed. I was good to head for the beach with my boards (surfing) and before doing so, as the battery wasn't that great any more I replaced it with a new one. The next time I started it after fitting the battery the dying fault was back!!!! In desperation I repositioned the crank position sensor wire into a different position and keyed the motor only to have it fire and die as usual, I keyed the motor a 2nd time and again it fired and died. In desperation I keyed the motor a 3rd time and it fired and ran normally. From then on it continued to start and run normally with every key turn. I also tried bringing the now insulated cam sensor wire together with the crank sensor wire to see if it would kill the motor as it previously had when the two wires met and found it did not stop the motor when the newly insulated wires were pushed together. Despite this I felt unable to trust the schizoid motor to stay cool for my surfing missions so I decided to test the crank sensor with a multimeter to see if it's resistance was the correct reading. The correct reading should have been between 200k and 500K and all as I could get on the meter while both the meters probes remained in contact with the contacts in the plug was a reading of 000. However, after releasing the negative probe, a number that changed drastically with every test I did would momentarily flash up on the meter, some numbers were drastically lower than 200k and others drastically higher. This you may think could indicate a faulty crank sensor? Alas that would have been all to simple. I was uncertain about the meter's resistance testing of the sensor and didn’t trust it, so I removed the crank sensor and took it to a garage where I had the mechanic do the same test with his multimeter. Every test shown a reading of exactly 304k!(which is within the normal range for the sensor) which meant as far as testing resistance in the sensor went it was reading normal. Without disturbing anything else on the vehicle I had removed, tested, and refitted the crank position sensor and guess what happened when I tried to start it? (to recap - the schizoid motor had been reliably firing and running normally with every key turn before I removed, tested, and refitted the crank position sensor) The very first attempt to start the motor after refitting the crank sensor resulted in a return to the motor firing and dying, which it has stayed stuck like despite me moving the crank sensor wire around into different positions. This why I suspect the fault lies somewhere within the crank position sensor or its wiring (possibly in the stretch to the ecu) Hence my request for help in these areas and to find a reader compatible with the vehicle in the hope it may find a fault code for the suspected sensor or sensor wiring.

 

1) In future posts break up your long paragraphs to make things easier to read. I did the same thing once and was told many members won't even look at a block of print like yours. Remember, many people are using smaller screens.

2) By chance did you get the names and model numbers of the 3 readers which didn't connect with your car? Were they cheap little things or what?

3) I got a CKP (Crankshaft Positioning Sensor) once in a 2005 Saab. Here the code was specific and I just ordered a replacement. Mine was of the "magnet pulse" variety and I am sorry to say the thought of measuring the failed CKP electrical properties never occurred to me.

What I did notice was that the magnet in the failed unit was very weak. It wouldn't hold onto the side of a metal trash bin. The replacement sensor hung on solidly. How's that for a thoroughly scientific test?

4) Everyone advises to identify a problem before buying parts. The mechanic's solid readings being acceptable AND the results of your wire crossing trials would have me looking carefully at the wires again.

Get the wiring diagrams for your car and indeed see if you can trace back to the ECU looking for damage. Goose (message) the wires as best you can during a period of smooth engine operation. You may stumble upon a break.

5) Do check for water intrusion at the ECU box as it's been known to happen.

6) Roughly where are you located? Maybe a member with a adequate reader is close.

 

Thanks for help. I can only remember the make of the last diagnostic system that failed to read any fault code information - it was a Snap On and looked advanced. The operator was a professional in auto diagnostics. He said the 1999 models didn't have the VIN number of the vehicle programmed into the ecu as models from 2000 had, and that was possibly a reason for his reader that looks for the VIN number of a vehicle having probs.
He said 1999 V70s have the unfortunate timing to be too early for the ecu tech that diagnostic reader's like his need to sync with a vehicle, but late enough to have ecu tech controlling the motor and all the sensors that can develop faults.
My location is near the city of Chester in England. The wet stormy weather here is stopping me from working on motor at pres coz I work on it on driveway outdoors.



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You should absolutely join Volvoforums.org.uk as there are many more members who participate. They often hook up with each other.

Also, look into the local Volvo Owners Club as those members get discounts from UK parts suppliers.

 

not sure I follow the complaint and the advise given with the ECU coding. Starting in 1996, cars started supporting the OBD2 code sets. These codes are divided into functional areas ie powertrain (P codes for emissions/transmission) chassis codes (stuff like airbags etc) and ABS codes - which pretty much line up to which computer is recording and reporting the faults. There are like 5 different protocols for reporting data so your reader would need to support the one used by your car. To note, from 96 to 03, Volvo used the ISO 9141 but by 06, moved to the CAN protocol. The other thing that goes on is that the manufacturers also started mapping proprieatary codes and interpreted specific OBD codes. So when choosing an OBD2 code reader, you need to consider which protocol your car(s) use (particularly if your cars are older than an 06, which functional areas you require (ie all readers do the P codes, not all do ABS or SRS) and finally whether you are interested in viewing proprietary codes. Generally the more expensive the device, the more code sets and protocols are supported but you can get a lot of value with a $29 Harbor Freight reader if you just want to view emissions codes. Finally you can step up to the manufacturers own tools like VIDA or VAG (VW/Audi) etc. These tools do all the OBD and proprietary codes plus have the ability to view/configure features in the software.

 

Thanks for help. I have now found the ecu location and opened the box to check if it had water in and found it dry.

When you look into the ecu box (when your standing at the front of vehicle looking towards the windscreen) there are two ecu's - one is for the engine and the other for the autobox - sitting side by side. How can you tell which is the ecu for the engine? Is it the ecu on the left or on the right?
Once identified I will be able to test continuity between the plug connecting the crank sensor to the wiring loom and the crank sensor wiring connecting pins in the ecu slot, which will reveal if there's a wiring fault in that section of the crank sensor wiring.

 

there is a part number on the unit that should tell you which is the ECU (engine control unit) and which is the TCU (transmission control unit). You can google your car model to find the part number (or search eBay as there's a market for people selling used computer modules.

 

Thanks, I'll try that to find the part number.