EGT reading

[pcv0856]

Just installed a new EGT probe on a continental 0-200 and its reading -99. Is there anything i have to reset or calibrate to get it to produce a normal reading? (Dynon EMS-D120)

 

[Dynon]

That's not normal. It should read ambient. One way to test the EMS is to short the two EGT pins together. It should read roughly ambient temperatures (a little warmer). -99 can mean that the probe is either not connected, or defective. You can also swap the leads with another probe's to figure out where the issues is (it can be in the harness too, for example.)

 

[Don_Patrick]

What would cause all of the CHT's and EGT's to read -99? They were working fine reading the ambiant hanger temps?

Don

 

[Dynon]

When do they change? Do they change gradually or immediately at engine start? Do the CHTs and EGTs react differently in speed? One thought - If you've connected them in reverse, the voltage differential that is generated by the rising temperature would cause you to see a temperature decrease, so that could explain it.

 

[Don_Patrick]

No engine start yet.

Went back to what I adjusted last, which was splicing into the Pin 15 of DB37, the Fuel flow 12V red wire.

With the splice and hookup to the cap volt convertors (not hooked to tank), I get the faulty reading on all CHTs and EGT's of -99. I removed the ground associated, no difference. I remove pin 15 from the DB37, replace the harness into the D180 and presto, Normal CHT and EGT reading the ambiant hanger temperature.

Any idea what could cause this?

Once the pin is removed, all good.

Thanks

 

[jakej]

Just maybe you were counting from the incorrect end of the dsub - can accidentally happen . Been there

 

[Don_Patrick]

I got it figured out...I re-did the connectors including the ground....reconnected, no issues

I removed the ground to verify....-99 returned.

Thsnks for he input.

Don