Coolant Temperature Sensor not reading on MSPNP2
#1
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After installing mspnp2 on my 96 stock engine. I have ran into a few problems I have not had any luck resolving or finding in the forums. Loaded the base maps and did some tuning to get it to run. Megasquirt does not read my coolant temperature sensor (CLT). It reads 180F and does not move even when it overheats based on the dash gauge. Here is what I`ve tried so far:
1. Calibrating the sensor based on information on DIY, MT.Net and M.Net. Set the resistor values based on the RX7_CLT ( S4 & S5) and the bias resistor to 1250,1550,2490,4890 Ohms to try and trouble shoot.
2. Replaced the sensor just in case, still nothing. When the OEM ECU was in I never had an overheating problem with fan engagement.
3. Opened the mspnp2 up to see if the R7 resistor was missing (got the MS used) everything is untouched. This was from my understanding something for MS1.
4. Measured the voltage at the sensor plug, got nothing, so I`m thinking it is a setting issue...
I have set the fans to always be on to avoid overheating, but want to get the MS and temperature to work together. Anyone had anything similar happen? Something they suggest I look into?
1. Calibrating the sensor based on information on DIY, MT.Net and M.Net. Set the resistor values based on the RX7_CLT ( S4 & S5) and the bias resistor to 1250,1550,2490,4890 Ohms to try and trouble shoot.
2. Replaced the sensor just in case, still nothing. When the OEM ECU was in I never had an overheating problem with fan engagement.
3. Opened the mspnp2 up to see if the R7 resistor was missing (got the MS used) everything is untouched. This was from my understanding something for MS1.
4. Measured the voltage at the sensor plug, got nothing, so I`m thinking it is a setting issue...
I have set the fans to always be on to avoid overheating, but want to get the MS and temperature to work together. Anyone had anything similar happen? Something they suggest I look into?
#2
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There is no voltage, the temp sensor is just a variable resistor, then it gets turned into a voltage inside the ECU. Check continuity between IAT connector and ECU connector, for both the signal wire to signal input pin, and from ground wire to sensor ground pin.
#5
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What's important about this for the OP is that there should in fact be voltage at the connector.
#7
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The TPS sensor doesn`t give a good reading either even after calibrating it manually and on tunerstudio. Reads 97% closed 99% open. Could this be related?
Since I have continuity could this still be a setting issue?
Should I use a custom inc. file or find the code for the sensor?
Could the basemap be wrong? I have 3.3 version with the basemap MS2E v3.3.1a MSPNP2-MM9697
Since I have continuity could this still be a setting issue?
Should I use a custom inc. file or find the code for the sensor?
Could the basemap be wrong? I have 3.3 version with the basemap MS2E v3.3.1a MSPNP2-MM9697
#11
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I tested the wirings for the TPS and they came out good. Did this back when I was testing the CLT.
I got used TPS to see if mine was bad after getting wierd reading from my multimeter. Same thing so both TPS are good.
I measured the voltage when on in the TPS and I dont get any. Also tried to calibrate the TPS and still at 98-99% for open and closed.
Was reading and saw MS3 had a TPS safety enabled in CANBUS, but doubt it applied to MSpnp2 specifically if a jumper needs to be jumped? I did not see or read anything about it. Car runs the same with or without the TPS, but the CLT is important for getting the car to run right.
At this point I'm wondering if there is anyone near Houston,TX that could take a look?
I got used TPS to see if mine was bad after getting wierd reading from my multimeter. Same thing so both TPS are good.
I measured the voltage when on in the TPS and I dont get any. Also tried to calibrate the TPS and still at 98-99% for open and closed.
Was reading and saw MS3 had a TPS safety enabled in CANBUS, but doubt it applied to MSpnp2 specifically if a jumper needs to be jumped? I did not see or read anything about it. Car runs the same with or without the TPS, but the CLT is important for getting the car to run right.
At this point I'm wondering if there is anyone near Houston,TX that could take a look?
#19
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So thanks to the suggestions to test the 3I and seeing that it had 5V I retested the continuity and found that it has continuity.
So I realized that I was testing the voltage using the tps harness ground instead of engine and concluded that the grounding wire is the culprit. Using the engine ground I now see 5v at the tps sensor connector.
Will look into where the ground is. Noticed that the ground wires in the front of the throttle body look corroded.
So I realized that I was testing the voltage using the tps harness ground instead of engine and concluded that the grounding wire is the culprit. Using the engine ground I now see 5v at the tps sensor connector.
Will look into where the ground is. Noticed that the ground wires in the front of the throttle body look corroded.
#20
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
So thanks to the suggestions to test the 3I and seeing that it had 5V I retested the continuity and found that it has continuity.
So I realized that I was testing the voltage using the tps harness ground instead of engine and concluded that the grounding wire is the culprit. Using the engine ground I now see 5v at the tps sensor connector.
Will look into where the ground is. Noticed that the ground wires in the front of the throttle body look corroded.
So I realized that I was testing the voltage using the tps harness ground instead of engine and concluded that the grounding wire is the culprit. Using the engine ground I now see 5v at the tps sensor connector.
Will look into where the ground is. Noticed that the ground wires in the front of the throttle body look corroded.
i have the same problem mega squirt isn’t reading the clt or iat sensor. I replaced the coolant sensor with an oem one with a new pigtail too.