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737 Problems - Fuel Light (Low Pressure) & A/T Not Functioning

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I have a couple minor issues with the TinMouse 737 in FSX, and I'm hoping there is someone out there who has experienced the same problem and has since overcome it.1) The fuel pumps are on, however the low pressure lights remain on, which I assume why the master caution light / fuel light remains on. I'm following the checklists ("FUEL PUMP SWITCHES - ON, All pumps on for tanks with fuel, LOW PRESS lights off), however I can't seem to get the darn lights to extinguish. Engine on, off... on the ground, flying... lights still on.2) I cannot get the auto throttle to engage. Auto pilot is already on, altitude and heading set... Set my speed, arm the A/T, click speed and nothing happens - I can't get it to engage.I am running V1.32 in Windows Vista 32.Help please!Thank you in advance.

1-try depowering the jet completely with the engines off (APU, ground power, and battery all off). If the lights are still on, it's a problem with DirectX and/or your video driver/card. If that's it, update DX9 and then your video driver.2-Is the PDCS programmed and set? If that's not it, put the throttles into the null zone at full throttle or idle (at the ends of travel the null zone should produce a stable unchanging value of 0 or 16383)...it could be a noisy pot spiking.

Bob Scott | President and CEO, AVSIM Inc
ATP Gulfstream II-III-IV-V

Sys1 (MSFS20+24/XPlane12+11): AMD 9800X3D, water 2x240mm, MSI MPG X670E Carbon, 64GB GSkill 6000/30, nVidia RTX4090FE
Alienware AW3821DW 38" 21:9 GSync, 2x4TB Crucial T705 PCIe5 + 2x2TB Samsung 990 SSD, EVGA 1000P2 PSU, 12.9" iPad Pro
Thrustmaster TCA Boeing Yoke, TCA Airbus Sidestick, Twin TCA Airbus Throttle quads, PFC Cirrus Pedals, Coolermaster HAF932 case

Sys2 (P3Dv5/v4): i9-13900KS, water 2x360mm, ASUS Z790 Hero, 32GB GSkill 7800MHz CAS36, ASUS RTX4090
Samsung 55" JS8500 4K TV@60Hz,
3x 2TB WD SN850X 1x 4TB Crucial P3 M.2 NVME SSD, EVGA 1600T2 PSU
Fiber link to Yamaha RX-V467 Home Theater Receiver, Polk/Klipsch 6" bookshelf speakers, Polk 12" subwoofer, 12.9" iPad Pro
PFC yoke/throttle quad/pedals with custom Hall sensor retrofit, Thermaltake View 71 case, Stream Deck XL button box

Sys3 (DCS/P3Dv4/ATS/ETS): AMD 7800X3D, MSI MPG X870E Carbon, Noctua NH-D15S, 64GB GSkill 6000/30, EVGA RTX3090
Alienware AW3420DW 34" 21:9 GSync, Corsair HX1000i PSU, 4TB Crucial T705 PCIe5 + 2TB Samsung 970Evo Plus,
TM TCA Officer Pack
, Saitek combat pedals, TM Warthog, TM RS300 FF wheel/pedals, Coolermaster HAF XB case

  • Author

Thanks for your reply Bob.1) When I cut all power, all lights go dark. When I start with a hot Cessna 172, then switch to the 737, everything looks fine initially, however once I throttle up, the low pressure lights come on.2) I didn't initially have the PDCS programmed... however when I tried, I still couldn't do anything with the auto throttle.It's something I'm doing, I'm sure. I'm going to look through the doc's again and keep trying :-)Again, thanks for your help.

1) When I cut all power, all lights go dark. When I start with a hot Cessna 172, then switch to the 737, everything looks fine initially, however once I throttle up, the low pressure lights come on.
All six of them? Just to confirm, the "on" position of the fuel pump switches is DOWN. How is your power configured? No off flags on the main panel? To get those lights you either need to have no fuel in the associated tank, or no power (the center tank lights also require the switch to be selected on).
2) I didn't initially have the PDCS programmed... however when I tried, I still couldn't do anything with the auto throttle.
Make sure these two lines are in the aircraft.cfgautothrottle_available=1autothrottle_arming_required=1Are you using our model from the V1.30 distributable?

Bob Scott | President and CEO, AVSIM Inc
ATP Gulfstream II-III-IV-V

Sys1 (MSFS20+24/XPlane12+11): AMD 9800X3D, water 2x240mm, MSI MPG X670E Carbon, 64GB GSkill 6000/30, nVidia RTX4090FE
Alienware AW3821DW 38" 21:9 GSync, 2x4TB Crucial T705 PCIe5 + 2x2TB Samsung 990 SSD, EVGA 1000P2 PSU, 12.9" iPad Pro
Thrustmaster TCA Boeing Yoke, TCA Airbus Sidestick, Twin TCA Airbus Throttle quads, PFC Cirrus Pedals, Coolermaster HAF932 case

Sys2 (P3Dv5/v4): i9-13900KS, water 2x360mm, ASUS Z790 Hero, 32GB GSkill 7800MHz CAS36, ASUS RTX4090
Samsung 55" JS8500 4K TV@60Hz,
3x 2TB WD SN850X 1x 4TB Crucial P3 M.2 NVME SSD, EVGA 1600T2 PSU
Fiber link to Yamaha RX-V467 Home Theater Receiver, Polk/Klipsch 6" bookshelf speakers, Polk 12" subwoofer, 12.9" iPad Pro
PFC yoke/throttle quad/pedals with custom Hall sensor retrofit, Thermaltake View 71 case, Stream Deck XL button box

Sys3 (DCS/P3Dv4/ATS/ETS): AMD 7800X3D, MSI MPG X870E Carbon, Noctua NH-D15S, 64GB GSkill 6000/30, EVGA RTX3090
Alienware AW3420DW 34" 21:9 GSync, Corsair HX1000i PSU, 4TB Crucial T705 PCIe5 + 2TB Samsung 970Evo Plus,
TM TCA Officer Pack
, Saitek combat pedals, TM Warthog, TM RS300 FF wheel/pedals, Coolermaster HAF XB case

On my installation, FS9 v.1.40, the fuel booster pump lights function correctly, that is they come on if a tank has fuel and the associated pump switch is off, and the Master Caution -- Fuel comes on. However, when you cancel the Master Caution it remains illuminated as Fuel, unlike the real aircraft. Seems to be a small glitch there, are you aware of it Bob?

  • Author

1) All six are initially on (Fuel Pump 1 & 2 above, then fuel Pump FWD and AFT 1 & 2) I can turn the main Fuel Pump 1 & 2 off and the associated lights go off, however I cannot get the lower four lights to turn off, regardless of whether or not the switches are on or off (Fuel Pump FWD and AFT 1&2). Here are a couple of links showing the panel configuration.http://i174.photobucket.com/albums/w111/tpeard/MainPanel.jpghttp://i174.photobucket.com/albums/w111/tpeard/OverheadPanel.jpg 2) I don't think the panel I was initally using had the A/T incorporated. I switched it for another panel with it enabled and it worked. The aircraft.cfg does have those two items listed.Thanks.

According to those 2 photos, you need to put your APU generator on the busses -- the 2 switches immediately below the blue APU GEN OFF BUS light, because right now your engines are not running and only the battery is powering the electrical system. The battery will quickly run down if you don't have a generator on the line. That might be the source of your problem with the booster pump low pressure lights.

  • Author

Hmm... the engines were running when I took the shot - I didn't catch that the light was on when I took the screenshot. I will run through the startup again next time I'm in the sim. I'm pretty sure the APU GEN OFF BUS light was off other times when I was still getting the low pressure lights for the fuel pumps. I'll try it again though.

According to those 2 photos, you need to put your APU generator on the busses -- the 2 switches immediately below the blue APU GEN OFF BUS light, because right now your engines are not running and only the battery is powering the electrical system. The battery will quickly run down if you don't have a generator on the line. That might be the source of your problem with the booster pump low pressure lights.
I looked at that initially as well but the engines are running (can't explain the EGT gauges not registering though...) and the engine generators are online...30A on 1, 40A on 2. There has to be something else funky going on.Rob Wilkinson
Tinmouse%2520Forum%2520sigpic061012.png
1) All six are initially on (Fuel Pump 1 & 2 above, then fuel Pump FWD and AFT 1 & 2) I can turn the main Fuel Pump 1 & 2 off and the associated lights go off, however I cannot get the lower four lights to turn off, regardless of whether or not the switches are on or off (Fuel Pump FWD and AFT 1&2).Here are a couple of links showing the panel configuration.http://i174.photobuc...d/MainPanel.jpghttp://i174.photobuc...erheadPanel.jpg2) I don't think the panel I was initally using had the A/T incorporated. I switched it for another panel with it enabled and it worked. The aircraft.cfg does have those two items listed.Thanks.
OK, the pictures spoke a thousand words. It appears to me that your battery bus is depowered. The EGT gauges run off the standby DC bus, which is tied to the batt bus in normal ops...and the boost pumps are powered off the battery bus directly. I would suspect the age-old FS battery bug is behind this, which is easily cured. In the FSUIPC misc tab, make sure the "Extend Battery Life" checkbox is ticked, and I recommend you place a value of 0 in the adjacent box to extend it indefinitely.

Bob Scott | President and CEO, AVSIM Inc
ATP Gulfstream II-III-IV-V

Sys1 (MSFS20+24/XPlane12+11): AMD 9800X3D, water 2x240mm, MSI MPG X670E Carbon, 64GB GSkill 6000/30, nVidia RTX4090FE
Alienware AW3821DW 38" 21:9 GSync, 2x4TB Crucial T705 PCIe5 + 2x2TB Samsung 990 SSD, EVGA 1000P2 PSU, 12.9" iPad Pro
Thrustmaster TCA Boeing Yoke, TCA Airbus Sidestick, Twin TCA Airbus Throttle quads, PFC Cirrus Pedals, Coolermaster HAF932 case

Sys2 (P3Dv5/v4): i9-13900KS, water 2x360mm, ASUS Z790 Hero, 32GB GSkill 7800MHz CAS36, ASUS RTX4090
Samsung 55" JS8500 4K TV@60Hz,
3x 2TB WD SN850X 1x 4TB Crucial P3 M.2 NVME SSD, EVGA 1600T2 PSU
Fiber link to Yamaha RX-V467 Home Theater Receiver, Polk/Klipsch 6" bookshelf speakers, Polk 12" subwoofer, 12.9" iPad Pro
PFC yoke/throttle quad/pedals with custom Hall sensor retrofit, Thermaltake View 71 case, Stream Deck XL button box

Sys3 (DCS/P3Dv4/ATS/ETS): AMD 7800X3D, MSI MPG X870E Carbon, Noctua NH-D15S, 64GB GSkill 6000/30, EVGA RTX3090
Alienware AW3420DW 34" 21:9 GSync, Corsair HX1000i PSU, 4TB Crucial T705 PCIe5 + 2TB Samsung 970Evo Plus,
TM TCA Officer Pack
, Saitek combat pedals, TM Warthog, TM RS300 FF wheel/pedals, Coolermaster HAF XB case

  • Author

Thanks Bob & everyone else for your help! My self conducted checkride went smooth - I'm really liking this plane! Again, thank you!

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