P1639: Vehicle ID (VID) Block Corrupted or Not Programmed (Ford)
Quick Answer
Safe to drive (short-term)
P1639 is a Ford-specific code that means the vehicle ID (VID) block in the powertrain control module (PCM) is not programmed or its data is corrupted. The VID block is the identity and configuration data the module is programmed with. It tends to show up after a PCM is replaced, reprogrammed or has its stored memory cleared. Other makes may use P1639 for something different, so confirm the definition for your make. It points at stored data, not at a failed sensor or part, and a generic OBD2 reader cannot write the fix.
- Severity
- Moderate · Electrical
- Estimated repair cost
- From €30 to €1350+, varies by vehicle
€30 or €1350, depending on your car.
- Diagnosis and code read with Ford-level software€30–€80
- Replace PCM and program it to the vehicle€450–€1350
A scan shows whether P1639 is really stored on your car, which codes sit next to it and how urgent each one is.
A scan needs a Bluetooth OBD2 adapter (Bluetooth LE on iPhone), about €25-60; the built-in demo runs without one. See which adapter to buy
What does P1639 mean?
P1639 is a electrical-related diagnostic trouble code classified as moderate severity.
What are the symptoms of P1639?
- Check engine light on
- Car usually starts and runs normally
- Code appears right after a PCM replacement, reprogramming or a memory reset
- Code returns after clearing, or cannot be cleared
- Emissions monitors stay incomplete after a reset
- A related configuration code such as P1635 (tyre or axle ratio out of range) may be stored with it
What causes P1639?
Replacement PCM fitted without the VID block being programmed
: high
Stored PCM memory cleared or lost, so the module no longer holds its vehicle identity
: high
Reprogramming that did not finish or was done with the wrong calibration or configuration data
: medium
Configuration data that does not match the vehicle's other modules
: medium
Replacement PCM that is not the correct part or is set up with the wrong vehicle configuration
: low
Is it safe to drive with P1639?
Generally yes, for short-term driving. In the documented cases the car started and ran normally, because the fault is in stored data and not in a part. The lit engine light and a code that will not clear can still fail an emissions inspection, and the data has to be reprogrammed with Ford-level software. Fix it soon.
How do you diagnose P1639?
- Read all stored codes and the freeze frame. Note whether P1635 or other configuration codes are stored with P1639.
- Work out what changed just before the code appeared: a PCM replacement, a reflash that did not finish or a memory reset. That history usually decides the repair.
- Check the 12V battery and charging voltage before any programming, and expect the workshop to keep stable power connected during the flash.
- Reprogram the PCM and its vehicle ID data with Ford's diagnostic software, using the correct calibration and the vehicle's configuration data. This is not possible with a generic OBD2 reader.
- After programming, clear the codes and complete a normal drive. A reset also returns the emissions monitors to incomplete, so allow time for them to finish before an inspection.
- If the code is still listed after programming, check whether it shows as a permanent code. Permanent codes cannot be erased with a scan tool by design, and drop out only after the car's own checks pass on later drives. If it is a normal stored code that keeps returning, the workshop has to find which stored data is missing or wrong.
How much does P1639 cost to fix?
| Repair | Parts Cost | Labor Cost | Total Estimate | DIY Difficulty |
|---|---|---|---|---|
| Diagnosis and code read with Ford-level software | €0–€0 | €30–€80 | €30–€80 | Professional |
| Reprogram the PCM and write the vehicle ID (VID) data | €0–€30 | €80–€250 | €80–€280 | Professional |
| Battery or charging check, or battery replacement, before programming | €60–€200 | €0–€50 | €60–€250 | Easy |
| Replace PCM and program it to the vehicle | €300–€1000 | €150–€350 | €450–€1350 | Professional |
Prices estimated as of October 2026. Costs vary by region, vehicle, and shop.
P1639 on specific vehicles
P1639 on Ford
Ford Edge (3.5 V6) · Ford Fusion (1.5 EcoBoost, 6F35 automatic)
Related diagnostic codes
Common questions about P1639
- What does P1639 mean?
- On Ford vehicles P1639 means the vehicle ID (VID) block is not programmed or its information is corrupted. The VID block is the identity and configuration data stored in the PCM. Other makes may use the number differently.
- Why did P1639 appear after a PCM replacement?
- A replacement PCM has to be programmed with the vehicle's identity data. If that step is skipped or fails, the module stores P1639. Reprogramming the PCM with Ford's software is how the VID block is written.
- Why does P1639 appear after the memory is cleared?
- In one published case, a Ford Edge stored P1639 after its keep-alive memory was cleared, because the module had lost its stored identity data. The article's fix was to reflash the PCM so the VID block could be reprogrammed.
- Can I drive with P1639?
- In the documented cases the vehicle started and ran normally. It is still a stored fault with a lit engine light, so plan to have it fixed soon, especially before an emissions inspection.
- Can I clear P1639 myself?
- Clearing only hides a normal stored code for a while if the data is still missing. A permanent code cannot be erased with a scan tool at all, and it drops out only after the car's own checks pass on later drives. The VID data itself has to be right.
- Will a generic OBD2 reader or phone app fix it?
- No. A generic reader can show the code and clear a normal stored one, but it cannot write the VID block. That needs Ford-level programming software.
Read our detailed guides
Sources
- legacy-www.motor.com legacy-www.motor.com/?p=14779
- en.wikipedia.org en.wikipedia.org/wiki/Ford_Edge
- diag.net diag.net/discussion/s7syexfzffumbxqfuhiaaqahw5