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GRT HP fuel sensor

Tankerpilot75

Well Known Member
I bought my RV7A two years ago this coming April 3rd. I had a long list of squawks at time of purchase that I've slowly been working my way through. The last item on the list was repair/replacement of an inaccurate fuel pressure sensor.

Several VAF members helped me try to get the original VDO 80 psi fuel pressure sensor working by custom adjustment of my EIS auxSF and auxOFF settings but that led no where. From that exercise I figured out the old sensor was toast and needed replacement.

I called GRT and ordered a new HPS-SS-01 fuel pressure sensor. They priority mailed me one and a week later I installed it. Unfortunately I couldn't get the appropriate readings on my EIS and after struggling for two days called GRT tech support. Several hours on the phone with Eric doing various tests confirmed my new sensor was bad. Sometimes even new equipment can be defective so they priority mailed me a new one. That added another two work days plus a weekend to my journey.

The new sensor arrived Monday and Tuesday I was back at the hangar (an hour's drive from my house) to install the new, new sensor. This time I was extremely careful installing the sensor and new connections Testing all connections for continuity and proper voltage. I once again powered up the EIS only to have incorrect AuxOFF readings. The EIS also shut down after a few minutes. I struggled again for two days second guessing what I could be doing wrong, finally gave up and called GRT tech support once again for help. Eric again was very helpful and we went through more checks not believing a second sensor could also be bad.

Finally Eric had me read him the model number of my latest sensor. That model number sparked both of our attention a little bit because it indicated a 4.5v sensor and I was powering it with the 12v line out of the EIS. Eric said he wanted to check something and would call me back within 30 minutes.

Guess what - I had been sent two incorrect sensors. Both were 4.5v sensors when I should have received an 8 - 30 volt sensor. I was literally frying the sensors with the 12v line feeding it which is why the EIS would shut down after a few minutes. It seems GRT had gotten the wrong voltage sensor from their supplier.

They are now ordering a new batch of sensors and have quarantined their current supply. I will say throughout this ordeal GRT has been very attentive to service and customer support. It's unfortunate they got in a bad batch of sensors and for me it's been a real challenge and time consuming effort to figure out. What I expected to be a half day job has turned into a two week effort and the plane is still down awaiting the correct part. Such is the life of an RV owner!!
 
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I have installed 3 GRT EFIS units now, one with an EIS 6000 system. There is defiantly a learning curve with many hours of button pushing and head scratching. Tech support is awesome and so are their products.

Cheers,
Phil :)
 
Your choice of course, but if you are getting impatient waiting, plenty of planes have been flown without fuel pressure sensors ever being installed.

Erich
 
I have one at home in the mail box waiting for me. Can you give me a heads up on what to look for? Thanks

Eric at GRT called me back this morning and told me they've ordered replacement sensors and that it will probably be two plus weeks before a replacement is sent to me.

I guess I could put a plug on the sensor's port and fly but I've got a few items I want to check out and this could be a good time to do them.

The bad GRT sensor has a SSI Technology part number of P51-100-S-B-I36-4.5v-000-000. If yours has that part number contact GRT and get on the replacement list.
 
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Oh well!

Thanks for the catch! You saved a lot of folks a lot of time.

Wish I could take credit for the "catch" but it was actually Eric at GRT trying hard to help me. My only complaint is that they're not offering me a "free" GRT Horizon HX or EX exchange for my old dual WS system as a "payment" for my "valuable" time spent trying to figure out why my replacement sensor wasn't working correctly. Now if they were truly "great" they'd offer to swap!!!

Oh well, it was worth a try.
 
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For those who may be wondering whether they have the correct pressure sensor:

The correct manufacturer part number for the HPS-SS-01 is

P51-100-G-B-I36-5V-R-000-000


The "5V" in the part number means it has a maximum voltage output of 5V. This particular part number is designed for a 8-30V power source.

Sensors marked "P51-100-S-B-I36-4.5V-000-000" should not be installed and will be destroyed if supplied from a voltage source greater than 5V. If you have received one of these sensors, Please contact GRT Avionics an exchange for the correct sensor.

Note: This only applies to part number HPS-SS-01. Customers using VDO fuel pressure sensors should disregard this information.
 
Good News

Queried GRT about their order status of replacement sensors. Eric emailed me back that GRT has received their replacement sensors and they're sending me one ASAP. Should be back in the air soon!
 
Welcome to VAF!

Eric,
welcome.gif
aboard the good ship VAF.

Always good to have direct contact to vendors support staff--------methinks you will generate a lot of contact from being here.
 
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