P1952 OBD Code
#1
07-02-2016, 01:04 PM
P1952 OBD Code
Hallo.
I have a problem with my 1995 Chevy Blazer.
While driving engine check lamp appears.
In addition engine started to stops itself when I did not put the gas and worked really unsteady (from 0-2000 RPM).
All of these happened after I´ve changed ignition plugs, cables, rotor and the cover (I did connect the cables in right order
).
Next day problem disappeared itself and then came back again after some time and disappeared again.
I went to the workshop anyway and they found the malfunction with code P1952.
The problem is that nobody knows what the code means!!
Please help!!! Anyone?
I have a problem with my 1995 Chevy Blazer.
While driving engine check lamp appears.
In addition engine started to stops itself when I did not put the gas and worked really unsteady (from 0-2000 RPM).
All of these happened after I´ve changed ignition plugs, cables, rotor and the cover (I did connect the cables in right order
).Next day problem disappeared itself and then came back again after some time and disappeared again
.I went to the workshop anyway and they found the malfunction with code P1952.
The problem is that nobody knows what the code means!!
Please help!!! Anyone?
#2
07-03-2016, 10:44 AM
I cannot find that code anywhere as a valid one, so I have to assume you don't have a P1952. Maybe the P1952 is an artifact of the scan tool that was being used or it was not copied correctly
but if problem started with changing spark plugs, wires, rotor, and distributor cap - then you may have a damaged (cracked porcelain) on a spark plug - or a spark plug wire that is not making connection or is internally damaged. You needto find out what you did to induce the problem.
I think you have no choice but to remove all parts you installed for a thorough inspection of electrical system. Test wires with OHM meter and make sure termials are clean and properly positioned in the boots. Look spark plugs for any cracks in porcelain (#3 is typically the one that gets cracked during installation).
I assume that you did not remove the distributor or try to turn it.
but if problem started with changing spark plugs, wires, rotor, and distributor cap - then you may have a damaged (cracked porcelain) on a spark plug - or a spark plug wire that is not making connection or is internally damaged. You needto find out what you did to induce the problem.
I think you have no choice but to remove all parts you installed for a thorough inspection of electrical system. Test wires with OHM meter and make sure termials are clean and properly positioned in the boots. Look spark plugs for any cracks in porcelain (#3 is typically the one that gets cracked during installation).
I assume that you did not remove the distributor or try to turn it.
#3
07-03-2016, 12:22 PM
I think the P1952 code means you need to take it to a different (better) shop.
Is your 1995 model "OBD-II"? Do the words "OBD-II Certified" appear on the emissions sticker on the fan shroud? Is the PCM located on top of the coolant tank on the passenger side, under the hood?
Is your 1995 model "OBD-II"? Do the words "OBD-II Certified" appear on the emissions sticker on the fan shroud? Is the PCM located on top of the coolant tank on the passenger side, under the hood?
#4
07-03-2016, 12:33 PM
Thanx very much for your reply.
And I did not remove the distributor. Only took out the rotor and put new one in exact same position.
The code was for sure P1952. I saw it with my own eyes on diagnostic scanner but maybe the scanner is giving the wrong code.
As far as I figured it out on forum I have OBD 1.5 in my 1995 model.
I´ve just ordered Craftsman 20899 Scan Tool Can Obd2&1
This one:
Craftsman - 20899 - CanOBD2&1 Scan Tool Kit with PC Software & Optional RepairSolutions® | Sears Outlet
Do you think this one will connect properly with my Blazer?
Right now the car is working fine.
I hope it will stay like this until the scanner will arrive.
The only problem now is fuel consumption. It takes 20l per 100km(75,7 galon/62,15 mile) witch I think is too much.
And I did not remove the distributor. Only took out the rotor and put new one in exact same position.
The code was for sure P1952. I saw it with my own eyes on diagnostic scanner but maybe the scanner is giving the wrong code.
As far as I figured it out on forum I have OBD 1.5 in my 1995 model.
I´ve just ordered Craftsman 20899 Scan Tool Can Obd2&1
This one:
Craftsman - 20899 - CanOBD2&1 Scan Tool Kit with PC Software & Optional RepairSolutions® | Sears Outlet
Do you think this one will connect properly with my Blazer?
Right now the car is working fine.
I hope it will stay like this until the scanner will arrive.
The only problem now is fuel consumption. It takes 20l per 100km(75,7 galon/62,15 mile) witch I think is too much.
#7
07-03-2016, 12:49 PM
It is difficult to tell what tools will connect with 1995. I think it is good sign if will connect to both OBD1 and OBD2. Just keep buying from places you can return.
Last edited by LesMyer; 07-03-2016 at 12:51 PM.
#8
07-03-2016, 01:31 PM
If your PCM is on top of the coolant recovery tank, yours is OBD-II. It should also have the 16 pin D shaped OBD-II connector under the dash on the driver's side, the 12 wire connector on the fuel injector assembly and other features from the 1996 models. That PCM will also work with any OBD-II scan tool.
If your PCM is inside, behind the glove box, it's OBD (or OBD-I if you insist, but it wasn't called that when they made it).
The scan tool you linked to will work for yours, and for all OBD-II vehicles (everything 1996 or newer and 1995 models that are "OBD-II Certified"). How much "manufacturer specific" data it understands depends on the tool. From the reviews, I see that one is unsupported and can't be updated, so I would have avoided that one. I'd look for a comparable price on the Innova version, the Innova 3140B, which has full support and I think has updates available. Revised after reading all of the reviews. Ignore the red text. It seems you can call Innova and get new software and updates for that one, so I take back my "I would avoid it" statement. I would recommend calling Innova and getting it updated as quickly as you can.
That scan tool will also work for 1993 and older (back to 1982 for some models) GM vehicles with the 12 pin ALDL connector. It says it works with "some 1994 and 1995 models." Usually that means it will work if your 1994-1995 has OBD (not OBD-II) and the old style rectangular 12 pin ALDL connector, but usually not with the D shaped 16 pin ALDL connector (the one that looks almost exactly like an OBD-II connector, but isn't OBD-II). Many scan tools that do the older OBD diagnostics get very confused by GM vehicles with the 16 pin ALDL connector, the one that looks like an OBD-II connector. They assume OBD-II with the cable for that connector, and OBD for the 12 pin ALDL connector, but arten't wired to read old style ALDL data from the 16 pin cable.
While I'll grudgingly grant that OBD-I is an actual thing, OBD-1.5 is nonsense.
If your PCM is inside, behind the glove box, it's OBD (or OBD-I if you insist, but it wasn't called that when they made it).
The scan tool you linked to will work for yours, and for all OBD-II vehicles (everything 1996 or newer and 1995 models that are "OBD-II Certified"). How much "manufacturer specific" data it understands depends on the tool. From the reviews, I see that one is unsupported and can't be updated, so I would have avoided that one. I'd look for a comparable price on the Innova version, the Innova 3140B, which has full support and I think has updates available. Revised after reading all of the reviews. Ignore the red text. It seems you can call Innova and get new software and updates for that one, so I take back my "I would avoid it" statement. I would recommend calling Innova and getting it updated as quickly as you can.
That scan tool will also work for 1993 and older (back to 1982 for some models) GM vehicles with the 12 pin ALDL connector. It says it works with "some 1994 and 1995 models." Usually that means it will work if your 1994-1995 has OBD (not OBD-II) and the old style rectangular 12 pin ALDL connector, but usually not with the D shaped 16 pin ALDL connector (the one that looks almost exactly like an OBD-II connector, but isn't OBD-II). Many scan tools that do the older OBD diagnostics get very confused by GM vehicles with the 16 pin ALDL connector, the one that looks like an OBD-II connector. They assume OBD-II with the cable for that connector, and OBD for the 12 pin ALDL connector, but arten't wired to read old style ALDL data from the 16 pin cable.
While I'll grudgingly grant that OBD-I is an actual thing, OBD-1.5 is nonsense.
Last edited by Racer_X; 07-03-2016 at 01:52 PM. Reason: Revised my "avoid" recommendation based on other reviews from the sears outlet site.
#9
07-04-2016, 05:20 AM
Racer_X thanks for info.
But I don´t think you are 100% right.
My 1995 model has computer over the cooling liquid tank but on the sticker stands "OBD I certified".
My OBD socket is 16-pins D-shape like OBD II, so this is some kind of "between" version.
Like a OBD I computer with OBDII socket, so some can call it OBD 1.5
But I don´t think you are 100% right.
My 1995 model has computer over the cooling liquid tank but on the sticker stands "OBD I certified".
My OBD socket is 16-pins D-shape like OBD II, so this is some kind of "between" version.
Like a OBD I computer with OBDII socket, so some can call it OBD 1.5
#10
07-04-2016, 01:31 PM
This is probably more than you ever wanted to know about 1995 model year GM cars and trucks.
I used to be a parts manager at a dealership. Here's what I can tell you for sure. 1995 GM vehicles left the factory in one of two possible configurations.
The early production vehicles left the factory without OBD-II. For the Blazers and S/T series trucks and SUV's with the 4.3L V6, they had ECM part # 16197427. If the factory installed an early production, non-OBD-II ECM in a 1995 model, it was installed behind the dash. The only mounting hardware for that ECM mounts it behind the dash. The only wiring harness with the correct connectors for that ECM is made to connect to it behind the dash. There is no mounting bracket and no wiring harness to move that ECM above the coolant recovery tank under the hood. That ECM connects to a diagnostic connector called an ALDL. I think all the S/T series trucks used the 16 pin ALDL connector, which is the same shape and size as the OBD-II DLC, but wired completely different. The onboard diagnostics for these early vehicles gives 2 digit DTC's, and uses a scan tool that supports earlier protocols (often misnamed "OBD-I"). The connector for an OBD-II scan tool will plug in to the 16 pin ALDL, but an OBD-II scan tool will not read any data from the ALDL on an early 1995 model with the early (not OBD-II certified) ECM.
The emissions label for these early production 1995 vehicles simply state "This vehicle conforms to U.S. EPA regulations applicable to 1995 model year new (cars | light-duty trucks)..." There is no use of the words "On board diagnostics," the letters "OBD" or the word "certified" on the emissions label for the early 1995 models.
Later production 1995 models were "OBD-II certified" vehicles. The first plants were converted in January of 1995, the last plants finished conversion in June or July, IIRC. Every plant that GM had made some model year 1995 "OBD-II certified" vehicles. It drives people nuts (especially parts guys) that there is no single cut off date or VIN cutoff between the old electronics and the OBD-II electronics. Every plant converted on a different date. GM "resolved" the issue with a bulletin that said (I'm paraphrasing here), if you see "OBD-II certified" on the emissions label, and the PCM is under the hood, use the 1996 parts catalog and service manuals. If you have one of these vehicles, you can save headaches by just telling the parts folks that you have an "early production 1996 model."
For the S/T series trucks and SUV's with the 4.3L V6, The "OBD-II certified" PCM is GM Part # 16244210. The factory always mounted that PCM under the hood, above the coolant recovery tank. The only brackets and the only wiring harnesses that fit that PCM are the ones for that mounting position.
The emissions label on the OBD-II late production 1995 vehicles have the words "OBD-II certified" somewhere on the label. OBD-II certified vehicles work with any OBD-II scan tool, and give "P series" 4 digit performance DTC's.
To the best of my knowledge, GM never made an emissions label that says "OBD-I Certified" and never made wiring harnesses and mounting hardware to install the early ECM above the coolant reservoir.
Perhaps someone "customized" something(s) on yours.
I used to be a parts manager at a dealership. Here's what I can tell you for sure. 1995 GM vehicles left the factory in one of two possible configurations.
The early production vehicles left the factory without OBD-II. For the Blazers and S/T series trucks and SUV's with the 4.3L V6, they had ECM part # 16197427. If the factory installed an early production, non-OBD-II ECM in a 1995 model, it was installed behind the dash. The only mounting hardware for that ECM mounts it behind the dash. The only wiring harness with the correct connectors for that ECM is made to connect to it behind the dash. There is no mounting bracket and no wiring harness to move that ECM above the coolant recovery tank under the hood. That ECM connects to a diagnostic connector called an ALDL. I think all the S/T series trucks used the 16 pin ALDL connector, which is the same shape and size as the OBD-II DLC, but wired completely different. The onboard diagnostics for these early vehicles gives 2 digit DTC's, and uses a scan tool that supports earlier protocols (often misnamed "OBD-I"). The connector for an OBD-II scan tool will plug in to the 16 pin ALDL, but an OBD-II scan tool will not read any data from the ALDL on an early 1995 model with the early (not OBD-II certified) ECM.
The emissions label for these early production 1995 vehicles simply state "This vehicle conforms to U.S. EPA regulations applicable to 1995 model year new (cars | light-duty trucks)..." There is no use of the words "On board diagnostics," the letters "OBD" or the word "certified" on the emissions label for the early 1995 models.
Later production 1995 models were "OBD-II certified" vehicles. The first plants were converted in January of 1995, the last plants finished conversion in June or July, IIRC. Every plant that GM had made some model year 1995 "OBD-II certified" vehicles. It drives people nuts (especially parts guys) that there is no single cut off date or VIN cutoff between the old electronics and the OBD-II electronics. Every plant converted on a different date. GM "resolved" the issue with a bulletin that said (I'm paraphrasing here), if you see "OBD-II certified" on the emissions label, and the PCM is under the hood, use the 1996 parts catalog and service manuals. If you have one of these vehicles, you can save headaches by just telling the parts folks that you have an "early production 1996 model."
For the S/T series trucks and SUV's with the 4.3L V6, The "OBD-II certified" PCM is GM Part # 16244210. The factory always mounted that PCM under the hood, above the coolant recovery tank. The only brackets and the only wiring harnesses that fit that PCM are the ones for that mounting position.
The emissions label on the OBD-II late production 1995 vehicles have the words "OBD-II certified" somewhere on the label. OBD-II certified vehicles work with any OBD-II scan tool, and give "P series" 4 digit performance DTC's.
To the best of my knowledge, GM never made an emissions label that says "OBD-I Certified" and never made wiring harnesses and mounting hardware to install the early ECM above the coolant reservoir.
Perhaps someone "customized" something(s) on yours.