tach and engine temp connection issue
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tach and engine temp connection issue Hello all,
Im new here. Im installing a 00 LS1 in 98 Volvo wagon. I have every wire accounted for, but I cannot figure out how I will make the stock volvo tach, and engine coolant temp gauge work. according to the factory diagram thels1 system (00 camaro ss) has one wire(C2 pin # 50 DK GRN/WHT) that comes from the pcm and feeds a processor in the instrument cluster information for engine temp, tach, and speed, the processor then sends the appropriate signal to each gauge, so do i need to get a camaro cluster and wire in that processor into my circuits? or ?? I also see a wire (C2 pin 10 WHT) which is the engine speed output and GM has that running to the EBCM (brake module) can I use this wire for the tach ?? In terms of the coolant gauge im lost. Thank you in advance, also if you can please email me direct as im not familiar with this forum stuff. tightfd@yahoo.com.
Ivan
Im new here. Im installing a 00 LS1 in 98 Volvo wagon. I have every wire accounted for, but I cannot figure out how I will make the stock volvo tach, and engine coolant temp gauge work. according to the factory diagram thels1 system (00 camaro ss) has one wire(C2 pin # 50 DK GRN/WHT) that comes from the pcm and feeds a processor in the instrument cluster information for engine temp, tach, and speed, the processor then sends the appropriate signal to each gauge, so do i need to get a camaro cluster and wire in that processor into my circuits? or ?? I also see a wire (C2 pin 10 WHT) which is the engine speed output and GM has that running to the EBCM (brake module) can I use this wire for the tach ?? In terms of the coolant gauge im lost. Thank you in advance, also if you can please email me direct as im not familiar with this forum stuff. tightfd@yahoo.com.
Ivan
The White Wire(Engine Speed) is your Tach Signal.
The one wire that you are talking about that feeds everything the Signals is known as the Serial Data Wire..the Oil Pressure, Speedo, Tach wires can be found seperate. You will have to splice onto the Red wire that comes from the Alternator to get the signal for that.
Here is how you do the Temp wire..
Get a 1998 F-body LS1 Temp Sensor(GM Part #12551708) and get a 3-Pin Connector identical to the one that is on the Throttle Position Sensor.
Wire in the bottom wires the same as the Connector that is currently in there..keep the 2 bottom wires on the sides that they are on, and then the third wire is the wire that goes to your Temp Gauge. I currently have mine setup like that, and I have no problems.
The reason you have to do this and the reason this works is cause the F-bodies that are 1998 and back use Analog Gauges, the 1999 and up use a BCM(Body Control Module) that sends one signal to the Gauges and it breaks it down digitally from there.
The one wire that you are talking about that feeds everything the Signals is known as the Serial Data Wire..the Oil Pressure, Speedo, Tach wires can be found seperate. You will have to splice onto the Red wire that comes from the Alternator to get the signal for that.
Here is how you do the Temp wire..
Get a 1998 F-body LS1 Temp Sensor(GM Part #12551708) and get a 3-Pin Connector identical to the one that is on the Throttle Position Sensor.
Wire in the bottom wires the same as the Connector that is currently in there..keep the 2 bottom wires on the sides that they are on, and then the third wire is the wire that goes to your Temp Gauge. I currently have mine setup like that, and I have no problems.
The reason you have to do this and the reason this works is cause the F-bodies that are 1998 and back use Analog Gauges, the 1999 and up use a BCM(Body Control Module) that sends one signal to the Gauges and it breaks it down digitally from there.
On The Tree
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The White Wire(Engine Speed) is your Tach Signal.
The one wire that you are talking about that feeds everything the Signals is known as the Serial Data Wire..the Oil Pressure, Speedo, Tach wires can be found seperate. You will have to splice onto the Red wire that comes from the Alternator to get the signal for that.
Here is how you do the Temp wire..
Get a 1998 F-body LS1 Temp Sensor(GM Part #12551708) and get a 3-Pin Connector identical to the one that is on the Throttle Position Sensor.
Wire in the bottom wires the same as the Connector that is currently in there..keep the 2 bottom wires on the sides that they are on, and then the third wire is the wire that goes to your Temp Gauge. I currently have mine setup like that, and I have no problems.
The reason you have to do this and the reason this works is cause the F-bodies that are 1998 and back use Analog Gauges, the 1999 and up use a BCM(Body Control Module) that sends one signal to the Gauges and it breaks it down digitally from there.
The one wire that you are talking about that feeds everything the Signals is known as the Serial Data Wire..the Oil Pressure, Speedo, Tach wires can be found seperate. You will have to splice onto the Red wire that comes from the Alternator to get the signal for that.
Here is how you do the Temp wire..
Get a 1998 F-body LS1 Temp Sensor(GM Part #12551708) and get a 3-Pin Connector identical to the one that is on the Throttle Position Sensor.
Wire in the bottom wires the same as the Connector that is currently in there..keep the 2 bottom wires on the sides that they are on, and then the third wire is the wire that goes to your Temp Gauge. I currently have mine setup like that, and I have no problems.
The reason you have to do this and the reason this works is cause the F-bodies that are 1998 and back use Analog Gauges, the 1999 and up use a BCM(Body Control Module) that sends one signal to the Gauges and it breaks it down digitally from there.
The three pin temp sensor is used only on the 98 F body and mounts in the same place the PCM sensor does on the 99+ engines. Problem is it won't do a thing for you on the Volvo as I doubt it will drive the volve temp gauge. My advise woud bo to try to find a place to install a Volvo temp sensor. Also. The LS PCM tach output would be the same as a 4cyl tach signal. So if your Volve had a 4cyl you may be in luck.
Re'
Re'
On The Tree
Joined: Jul 2006
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From: great white northeast
I used a Volvo temp sensor in the cylinder head (side with the unused sensor location). Dakota Digital makes a tach signal converter that will interface with the Volvo tach. Can be programed for any combination. About 80 bucks. I see that by 98 the Volvo tach runs off the ECU and not the primary side of the coil like the earlier ones did. It IS very possible that your tach will work just fine off the GM wiring.
Buy some tuning software like EFIlive that can change the tach signal if needed. You will need it anyway if you intend to keep your ride OBD2 compliant.
Buy some tuning software like EFIlive that can change the tach signal if needed. You will need it anyway if you intend to keep your ride OBD2 compliant.
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coolant temp gauge I used a Volvo temp sensor in the cylinder head (side with the unused sensor location). Dakota Digital makes a tach signal converter that will interface with the Volvo tach. Can be programed for any combination. About 80 bucks. I see that by 98 the Volvo tach runs off the ECU and not the primary side of the coil like the earlier ones did. It IS very possible that your tach will work just fine off the GM wiring.
Buy some tuning software like EFIlive that can change the tach signal if needed. You will need it anyway if you intend to keep your ride OBD2 compliant.
Buy some tuning software like EFIlive that can change the tach signal if needed. You will need it anyway if you intend to keep your ride OBD2 compliant.
Thanks for the info. So I believe the tach isssue is figured out, but the coolant temp gauge issue is a problem I was thinking of doing what you suggested above, however i wanted to run a test to see how the stock volvo gauge works, here is what happened. I know that the volvo system uses the ECT sends signal to the PCM, and then the PCM sends a signal to one wire of the three of the gauge in the instrument cluster. So I checked the gauge, and there is power, ground and the last wire (the one that was connected to the Volvo PCM) is signal, should be simple. When I turn on the key the gauge swings to the middle, then pegs to hot and then goes to full cold, I assume this is a self check. So now I assume that if I ground the sensor wire it should read full hot... it does not move, so I put power to that wire, no change, I checked and there is 7.7Volts there when using a digtial volt meter. So the question is what kind of signal is is the Stock Volvo PCM sending to the coolant temp gauge in the cluster to show the temp of the engine?? Thanks Ivan
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Verdad Gallardo On The Tree
Joined: Jul 2006
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From: great white northeast
You should be able to cut into the yellow/white from A14 on your cluster and with the key on try around 150 ohm resistor to see where your guage will be. Once you find where your temp guage will be in the center, then look for a suitable coolant sensor that shows "that many" ohms at running temp.
If I get a vehicle in the shop the next few days I'll post it for you. That Y/W wire will partially ground the guage.
If I get a vehicle in the shop the next few days I'll post it for you. That Y/W wire will partially ground the guage.
