Sponsored

Gladiator won’t start after sitting for two days.

flynhome

Member
First Name
Joe D
Joined
Dec 4, 2024
Threads
2
Messages
5
Reaction score
4
Location
Prescott, AZ
Vehicle(s)
2024 Gladiator
Occupation
Retired
After not driving vehicle for two days or more, upon pushing start button;
nothing, acts like dead battery. Note that the brake pedal is very hard to depress. Checked battery, 12.7 volts If I wait 15 minutes vehicle starts immediately. My thought is because initially I am unable to depress the brake pedal down this causes the problem. Does this make sense? Question is what causes brake pedal to be rigid.
Sponsored

 

ShadowsPapa

Well-Known Member
First Name
Bill
Joined
Oct 12, 2019
Threads
247
Messages
40,463
Reaction score
53,908
Location
Runnells, Iowa
Vehicle(s)
'25 JTMX, '23 JLU 4xe, '82 SX4, '73 Javelin
Occupation
Retired auto mechanic, frmr gov't ntwrk security admin
Vehicle Showcase
3
After not driving vehicle for two days or more, upon pushing start button;
nothing, acts like dead battery. Note that the brake pedal is very hard to depress. Checked battery, 12.7 volts If I wait 15 minutes vehicle starts immediately. My thought is because initially I am unable to depress the brake pedal down this causes the problem. Does this make sense? Question is what causes brake pedal to be rigid.
Loss of vacuum. Likely a leak at the check valve in the booster.
If you press the brake pedal REALLY REALLY HARD, can you get it to start?
 
OP
OP

flynhome

Member
First Name
Joe D
Joined
Dec 4, 2024
Threads
2
Messages
5
Reaction score
4
Location
Prescott, AZ
Vehicle(s)
2024 Gladiator
Occupation
Retired
Loss of vacuum. Likely a leak at the check valve in the booster.
If you press the brake pedal REALLY REALLY HARD, can you get it to start?
I have pushed quite hard or a least as hard as I dare without causing other issues
 

Jteakus

Well-Known Member
First Name
Teakus
Joined
Feb 19, 2022
Threads
19
Messages
1,811
Reaction score
3,274
Location
Oil City, LA
Vehicle(s)
2020 JLURD, 2022 JTRD, 2017 JKU, 1998 TJ, 1983 CJ-7
Build Thread
Link
Vehicle Showcase
1
Bill has gone "all in" on the color green.
 

Sponsored

Hootbro

Well-Known Member
First Name
Don
Joined
Apr 13, 2019
Threads
57
Messages
10,194
Reaction score
19,968
Location
Delaware
Vehicle(s)
2025 Gladiator Sport
Gladiator uses an electric vacuum pump to build vacuum. Even off, the brake booster still should retain vacuum for a couple pumps unless as @ShadowsPapa mentioned, the check valve or booster is leaking.

As to the brake switch, it is actually a three wire brake pedal travel sensor rheostat that sends the brake signal through the ABS module and out onto CAN bus for the BCM, PCM and RFH use for the start circuit.

The stop lamps use the same brake pedal travel sensor circuit. If your brake lamps are coming on, then that brake pedal travel circuit is fine and would look elsewhere in the start circuit. IMHO, the brake booster pressure is a secondary concern.

Jeep Gladiator Gladiator won’t start after sitting for two days. Brake PedaL sENSOR
 

Attachments

Jteakus

Well-Known Member
First Name
Teakus
Joined
Feb 19, 2022
Threads
19
Messages
1,811
Reaction score
3,274
Location
Oil City, LA
Vehicle(s)
2020 JLURD, 2022 JTRD, 2017 JKU, 1998 TJ, 1983 CJ-7
Build Thread
Link
Vehicle Showcase
1
@Hootbro, I haven't seen a Cylon since the late 70's
 

gonemad

Well-Known Member
Joined
Jul 24, 2024
Threads
15
Messages
419
Reaction score
727
Location
fringes of RTP
Vehicle(s)
’25 JT Rubicon, '24 FLHP Road King police
Occupation
retired headhunter
My 2024 did this once with just 6000 on the clock.

I just mashed the snot out of the brake pedal, that didn’t want to be mashed, with my size 14 wide clodhoppers, and it fired right up.

It might have done this another time or two.

Just mash it. Mash it good.

Jeep Gladiator Gladiator won’t start after sitting for two days. 1753829734109-ev
 

Hootbro

Well-Known Member
First Name
Don
Joined
Apr 13, 2019
Threads
57
Messages
10,194
Reaction score
19,968
Location
Delaware
Vehicle(s)
2025 Gladiator Sport

Sponsored

OP
OP

flynhome

Member
First Name
Joe D
Joined
Dec 4, 2024
Threads
2
Messages
5
Reaction score
4
Location
Prescott, AZ
Vehicle(s)
2024 Gladiator
Occupation
Retired
He must have got it started and is driving now.
He must have got it started and is driving now.
yep,started right up this morning, only have the issue if vehicle isn’t driven for two days or more. Almost due for service will address problem with dealer at that time. Thanks for all the response.
Sponsored

 
 







Top