Help with Trans Code please
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Help with Trans Code please
Hello! I have a 2008 Chevy Silverado with 331,000 miles on it. You see, it was my husbands. He died May 1st of this year. He was a master mechanic. The irony starts here.
I love the truck and I took it to the dump to recycle all of the batteries, used oil and brake pads. While driving there, I noticed the RPMs were higher than they should have been at 60 mph, but I pulled over to check it out because it was whining to much. I continued on to the dump and made it there perfectly! I'm not an idiot when it comes to cars and my husband used to get mad if I would change my own oil because he was taken too long.
On the way back the RPMs are 5-6,000 at 22 mph and the trans is not switching gears. I did not dare go any faster. The transmission was stuck 2nd gear. I can feel and see the flip from 1st to 2nd, but then it is stuck. I went 22 mph all the way home for 28 miles.
I got out of the truck and the transmission oil is black. I'm thinking, WTF, really? I really don't have time for this. I took out my snap on code reader and the transmission code is P1816. I've read up on it but I don't know where to start. Should I change the fluid first or the NSS switch thing? I bought a new filter and transmission oil but my brother said that if it's never been changed, leave it alone because that could mess things up. I'm thinking to myself, "How more messed up could it really get?" I'm a teacher and I'm not paying insane amounts of money for something to be fixed when I can start this process. I'm really not paying because I don't have any money to spare and that's the sad truth. Any advice would be appreciated and I am grateful that you read this.
Here's what the code means:
P1816 code means the Transmission Fluid Pressure (TFP) Valve Position Switch is indicating Park/Neutral but sees a Drive ratio, pointing to a transmission control issue, often related to the Neutral Safety Switch (NSS), solenoid pack, or wiring, causing hard shifts, no-starts, or slipping; start by checking fluid/wiring, then inspect/adjust the NSS and consider solenoids or TCM.
Common Causes
Faulty TFP Valve Position Switch/Neutral Safety Switch (NSS): The switch sends incorrect signals about gear selection.
Wiring Issues: Damaged, corroded, or loose wires/connectors to the switch or solenoids.
Solenoid Malfunction: A shift solenoid, especially the torque converter clutch (TCC) solenoid, failing.
Low/Dirty Transmission Fluid: Inadequate fluid can affect pressure and sensor readings.
Valve Body Problems: Sticking valves or internal issues within the valve body.
Troubleshooting Steps
Check Fluid: Verify transmission fluid level and condition; change if dirty.
Inspect Wiring: Look for frayed wires, corrosion, or loose connections on the transmission.
Test/Adjust NSS: A common fix is replacing or adjusting the neutral safety switch on the side of the transmission, ensuring it aligns correctly for Park/Neutral starting.
Scan Tool Data: Use a scanner to monitor TFP switch and solenoid data for real-time faults.
Consider Solenoids/TCM: If wiring and fluid are good, the shift solenoid pack or even the Transmission Control Module (TCM) might need attention.Quote Reply
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I love the truck and I took it to the dump to recycle all of the batteries, used oil and brake pads. While driving there, I noticed the RPMs were higher than they should have been at 60 mph, but I pulled over to check it out because it was whining to much. I continued on to the dump and made it there perfectly! I'm not an idiot when it comes to cars and my husband used to get mad if I would change my own oil because he was taken too long.
On the way back the RPMs are 5-6,000 at 22 mph and the trans is not switching gears. I did not dare go any faster. The transmission was stuck 2nd gear. I can feel and see the flip from 1st to 2nd, but then it is stuck. I went 22 mph all the way home for 28 miles.
I got out of the truck and the transmission oil is black. I'm thinking, WTF, really? I really don't have time for this. I took out my snap on code reader and the transmission code is P1816. I've read up on it but I don't know where to start. Should I change the fluid first or the NSS switch thing? I bought a new filter and transmission oil but my brother said that if it's never been changed, leave it alone because that could mess things up. I'm thinking to myself, "How more messed up could it really get?" I'm a teacher and I'm not paying insane amounts of money for something to be fixed when I can start this process. I'm really not paying because I don't have any money to spare and that's the sad truth. Any advice would be appreciated and I am grateful that you read this.
Here's what the code means:
P1816 code means the Transmission Fluid Pressure (TFP) Valve Position Switch is indicating Park/Neutral but sees a Drive ratio, pointing to a transmission control issue, often related to the Neutral Safety Switch (NSS), solenoid pack, or wiring, causing hard shifts, no-starts, or slipping; start by checking fluid/wiring, then inspect/adjust the NSS and consider solenoids or TCM.
Common Causes
Faulty TFP Valve Position Switch/Neutral Safety Switch (NSS): The switch sends incorrect signals about gear selection.
Wiring Issues: Damaged, corroded, or loose wires/connectors to the switch or solenoids.
Solenoid Malfunction: A shift solenoid, especially the torque converter clutch (TCC) solenoid, failing.
Low/Dirty Transmission Fluid: Inadequate fluid can affect pressure and sensor readings.
Valve Body Problems: Sticking valves or internal issues within the valve body.
Troubleshooting Steps
Check Fluid: Verify transmission fluid level and condition; change if dirty.
Inspect Wiring: Look for frayed wires, corrosion, or loose connections on the transmission.
Test/Adjust NSS: A common fix is replacing or adjusting the neutral safety switch on the side of the transmission, ensuring it aligns correctly for Park/Neutral starting.
Scan Tool Data: Use a scanner to monitor TFP switch and solenoid data for real-time faults.
Consider Solenoids/TCM: If wiring and fluid are good, the shift solenoid pack or even the Transmission Control Module (TCM) might need attention.Quote Reply
Report ••• Awaiting approval before being displayed publicly.
Write your reply...
Post reply
=1247&hash=c7a508baf3b223b80d23aae210c225cb]Attach filesShare:
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