Ford P1702 Code: Transmission Range Sensor Circuit Intermittent
Ford's gear selector position signal drops out now and then, so the PCM briefly loses track of your gear.
At a glance
Severity: Moderate
- Meaning
- Transmission Range Sensor Circuit Intermittent
- System
- Transmission · Powertrain
- Safe to drive?
- With caution
- Typical repair cost
- $0–$450
- DIY difficulty
- Moderate
The transmission range (TR) sensor tells the PCM which position the shift lever is in: Park, Reverse, Neutral, Drive or a manual range. It also enables the starter in Park and Neutral and turns on the backup lights. On Ford rear-drive automatics such as the 4R70W, 4R100/E4OD and 5R55 family, it sits on the left side of the case at the manual lever shaft, where road spray and heat attack the connector; front-drive units like the AX4N and CD4E have it at the shift lever on top of the case. P1702 means the signal was lost or became invalid for a moment and then came back. Unlike a hard failure, the fault is intermittent, so the diagnosis is all about catching the dropout: a loose connector, a sensor that is worn or slightly out of adjustment, or a harness that chafes when the drivetrain moves. This code belongs to US-market Ford trucks, vans and sedans of the EEC-V era.
Can I keep driving? Usable with care. Expect occasional harsh engagements or wrong-gear behavior; if the vehicle ever fails to crank in Park or the gear indicator jumps while driving, have it fixed before relying on it, and always set the parking brake.
How to read P1702
- P Powertrain
- 1 Manufacturer-specific
- 7 Transmission
- 02 Specific fault
Symptoms
- Gear indicator (PRNDL) on the cluster flickers or goes blank
- Starter intermittently won't engage in Park but works in Neutral
- Backup lights flicker or stay off in Reverse
- Harsh engagement or a flare between gears, sometimes stuck in a limp gear until restart
- Cruise control drops out without reason on some models
Possible causes
Ranked by how often each cause is behind this code (editorial estimate).
- Corroded, loose or water-filled TR sensor connector
- Worn TR sensor contacts giving dead spots between detents
- TR sensor or shift cable/linkage out of adjustment, so the lever rests between positions
- Harness chafed on the transmission, crossmember or transfer case, or heat-damaged near the exhaust
- Worn shift linkage bushings, especially on column shifters
- PCM input fault
Diagnosis step by step
Watch TR data while moving the lever
Engine off, key on, parking brake set. Watch the TR PID while slowly moving the lever through every position and back. The reading should step cleanly; any flicker, blank or wrong position at a detent pinpoints the fault.
Tools: OBD-II scanner
Check shifter and indicator alignment
Make sure each detent in the shifter matches the indicator and the lever on the transmission. Worn bushings or a stretched cable can leave the manual lever between detents, which the PCM sees as an invalid position.
Tools: Flashlight
Inspect the connector and harness
Unplug the TR connector at the case and look for green corrosion, water, spread terminals or melted insulation near the exhaust. Follow the harness along the transmission for rub-through spots and secure it.
Tools: Flashlight, Gloves
Wiggle test
With the TR PID on screen, flex the harness and connector while someone holds the lever in Drive. A dropout while wiggling identifies the wiring, not the sensor.
Tools: OBD-II scanner
Check or reset sensor alignment
If the sensor was disturbed, loosen the bolts and set it with Ford's TR alignment tool or the specified method with the lever in Neutral. Recheck the readings in every position afterward.
Tools: Screwdriver
Measure the sensor against its chart
Using the service chart for your transmission, check resistance or voltage for each position. A reading that jumps or opens at a certain lever angle confirms a worn sensor that needs replacement.
Tools: Multimeter
Where the parts are
- 1Battery
- 2Alternator
- 3Engine computer (ECM)
- 4CAN bus
- 5Transmission
- 6Wheel speed sensor
- 7High-voltage battery
Repair options & costs
| Repair | DIY? | Estimated cost |
|---|---|---|
| Clean and seal TR connector, repair terminals | Yes | $0–$120 |
| Adjust TR sensor or shift cable | Yes | $0–$150 |
| Replace shift linkage bushings | Yes | $20–$180 |
| Replace TR sensor | No | $150–$450 |
| Repair chafed transmission harness | No | $120–$400 |
Rough US estimates for parts and labor; shop rates vary by region. Not a quote.
Emissions / smog test impact
Depends
Transmission range codes don't always turn on the check engine light. If the light is on, the vehicle fails a US OBD emissions test; if P1702 is stored without the light, most test stations won't reject it.
Frequently asked questions
Why does my Ford sometimes not start in Park?
The TR sensor has to confirm Park or Neutral before the starter is allowed to crank. When its contacts or connector drop out, the PCM or starter circuit doesn't see Park, so nothing happens. Shifting to Neutral often works, which is a strong hint.
Is P1702 the same as P0705?
They're closely related. P0705 is the generic circuit malfunction for the range sensor, while Ford's P1702 specifically flags an intermittent dropout. The testing overlaps, but P1702 calls for more wiggle testing and alignment checks.
Can a misadjusted shift cable cause P1702?
Yes. If the lever on the transmission doesn't match the detents in the cabin, the sensor sits on the edge between two positions and flickers. Adjusting the cable or linkage can cure the code without a new sensor.
Will a bad range sensor damage the transmission?
Not directly, but wrong range information can cause harsh engagements and wrong shift commands. Repeated harsh engagements aren't good for clutches and mounts, so don't ignore it.
Sources
- Manufacturer public service information (cross-checked)
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